4l60e - No 3-4, but doesn't seem like clutches.
10-17-2016, 10:19 AM
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4l60e - No 3-4, but doesn't seem like clutches. 4l60e behind the 5.3 in my frankenrunner (we call it the Choda-Runner). First test drive (street), I was getting a 500rpm flare on 2-3 shift. Dumped in some Lucas transmission fixer snake oil and it cleaned it right up. I chalked it up to bad trans fluid. Shifts are all smooth and grab nice at all RPM.
Took it out last night for it's first test on the trail. About half way through the trail, I went to pop it in reverse and noticed the shifter lever was binding out on the top of the trans a little. Put in reverse, and hit the gas. It bucked like a retard. Try again, same thing. Buddy tells me my reverse lights are flickering, so I figure the trans must have moved up a little and on torque, was causing the shifter cable to stretch and dump it back into park.
No problem. Just hold onto the shifter just right and back up.
On a faster stretch of trail, (in OD on the shifter), I noticed commanded gear was 3rd, but I was clearly in second, and my TCC slip was reading -2600 (engine RPM 2200, in 4L). I didn't know what to think, so just went faster. When trans commanded 4th, I lost all power out the trans. Manually shift it into the 3 position, and it dumps back into 2 and won't even attempt to shift to 3 (ECM commands 3, but clearly never leaves 2).
On the way home I had LOTS of time to test stuff, as it's normally a 40 minute drive but I couldn't get past 2nd gear.
Shift position:
1 - 1st gear start and holds to any RPM.
2 - 2nd gear start and holds.
3 - Normal shift pattern through 1-2, 3 is commanded but never shifts.
4 - Normal shift patter, but never get 3rd, and when we're going fast enough for 4, it finally shifts out of second and then I lose all transmission output power. Like in neutral.
Trans was a touch warm at the time as I hadn't installed a secondary cooler yet. 108C, which really isn't that hot though. I figured at this point that the 3rd accumulator wasn't able to overcome the 2nd piston, which explains why I couldn't get out of 2nd and afaik, the 3rd accumulator is the only common denominator between the 2-3 shift, and having OD available at all, as 3rd accum feeds the 3-4 clutches (right?)
This morning, I hopped in truck to get coffee. Shifter was MUCH smoother. Still binding but nowhere near as bad. First run out the driveway, no 3 or 4. Stop at the light and go again, shifts perfect through all gears. Got all the way to my coffee and home with crisp shifts and OD TCC lockup.
So wtf? My original thought was the 3rd accumulator, mainly because this problem seems clearly a hydraulic one, especially in that it still persisted for the first run of the morning, but went completely away after cycling through the gears once. I can't see how busted 3-4 frictions could cause this. Also, fluid temp is now cold, and thus more viscous. A leaking 3rd accum could potentially work fine when cold, but be unable to overcome the 2nd piston when hot.
BUT, the trans shifted perfectly in all gears, after cycling through a full shift pattern this morning, and this morning the shifter itself isn't binding (much).
Am I on the right track with the 3rd accumulator, or is there any way it's something as simple as my shifter not quite syncing with the detents in the trans?
Took it out last night for it's first test on the trail. About half way through the trail, I went to pop it in reverse and noticed the shifter lever was binding out on the top of the trans a little. Put in reverse, and hit the gas. It bucked like a retard. Try again, same thing. Buddy tells me my reverse lights are flickering, so I figure the trans must have moved up a little and on torque, was causing the shifter cable to stretch and dump it back into park.
No problem. Just hold onto the shifter just right and back up.
On a faster stretch of trail, (in OD on the shifter), I noticed commanded gear was 3rd, but I was clearly in second, and my TCC slip was reading -2600 (engine RPM 2200, in 4L). I didn't know what to think, so just went faster. When trans commanded 4th, I lost all power out the trans. Manually shift it into the 3 position, and it dumps back into 2 and won't even attempt to shift to 3 (ECM commands 3, but clearly never leaves 2).
On the way home I had LOTS of time to test stuff, as it's normally a 40 minute drive but I couldn't get past 2nd gear.
Shift position:
1 - 1st gear start and holds to any RPM.
2 - 2nd gear start and holds.
3 - Normal shift pattern through 1-2, 3 is commanded but never shifts.
4 - Normal shift patter, but never get 3rd, and when we're going fast enough for 4, it finally shifts out of second and then I lose all transmission output power. Like in neutral.
Trans was a touch warm at the time as I hadn't installed a secondary cooler yet. 108C, which really isn't that hot though. I figured at this point that the 3rd accumulator wasn't able to overcome the 2nd piston, which explains why I couldn't get out of 2nd and afaik, the 3rd accumulator is the only common denominator between the 2-3 shift, and having OD available at all, as 3rd accum feeds the 3-4 clutches (right?)
This morning, I hopped in truck to get coffee. Shifter was MUCH smoother. Still binding but nowhere near as bad. First run out the driveway, no 3 or 4. Stop at the light and go again, shifts perfect through all gears. Got all the way to my coffee and home with crisp shifts and OD TCC lockup.
So wtf? My original thought was the 3rd accumulator, mainly because this problem seems clearly a hydraulic one, especially in that it still persisted for the first run of the morning, but went completely away after cycling through the gears once. I can't see how busted 3-4 frictions could cause this. Also, fluid temp is now cold, and thus more viscous. A leaking 3rd accum could potentially work fine when cold, but be unable to overcome the 2nd piston when hot.
BUT, the trans shifted perfectly in all gears, after cycling through a full shift pattern this morning, and this morning the shifter itself isn't binding (much).
Am I on the right track with the 3rd accumulator, or is there any way it's something as simple as my shifter not quite syncing with the detents in the trans?
10-17-2016, 10:30 AM
#2
Staging Lane
Join Date: Oct 2016
Location: Meridian MS
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Good morning,
Your 3/4 clutches are wore out completely. You will have to disassemble the transmission and rebuild to fix this issue. (New Clutches, Frictions Plates, Corvette Servo, Trans-Go 4L60e Shift Kit, 10 vane pump [13 vanes tend to fracture/break], and purchase a radiator style Transmission Cooler.
This should take care of all future issues.
Take care,
Eddie
Your 3/4 clutches are wore out completely. You will have to disassemble the transmission and rebuild to fix this issue. (New Clutches, Frictions Plates, Corvette Servo, Trans-Go 4L60e Shift Kit, 10 vane pump [13 vanes tend to fracture/break], and purchase a radiator style Transmission Cooler.
This should take care of all future issues.
Take care,
Eddie
10-17-2016, 10:43 AM
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Sorry if this is ignorant, but why does it shift perfectly though all gears this morning after cycling through all the gears once? From what I understand if the 3-4 clutches, if they're burnt to the point I get no power transmission, they shouldn't grab perfectly now...?
Hell, they shifted perfectly in the donor truck, which is 2000lbs heavier, and had zero problem shifting for the first hour or so on the trail. Just can't wrap my head around how they can work perfectly, and then not at all, and then perfectly again.
Also seems real strange to me that there was zero power transfer coming out of the driveway, but then perfect on all subsequent starts. I hammered the crap outta it on the way home and zero issues. TCC slip was bang on where I expected, and held tons of power on the last WOT run before I got home.
Am I missing something about their operation? (I hate just throwing parts at a problem without first understanding it. I want to know exactly what's going on inside any of my hardware).
Or.. Are you just giving me the first answer you found on the Googler? I've already been told it's the 3-4 frictions, but so far none of the guys who's said that, has been able to explain why I get perfect shifting most of the time, nor are they able to explain how burnt 3-4 frictions causes the trans to never even attempt to shift to third. As I said, the ECM commands 3rd, but trans stays in second. When ECM commands 4th, THAT's when I get neutral. Everything I've read about burned 3-4 says I should get zero power transfer in 3rd or 4th, but no one ever says anything about the trans not even attempting to shift to 3rd when commanded.
Hell, they shifted perfectly in the donor truck, which is 2000lbs heavier, and had zero problem shifting for the first hour or so on the trail. Just can't wrap my head around how they can work perfectly, and then not at all, and then perfectly again.
Also seems real strange to me that there was zero power transfer coming out of the driveway, but then perfect on all subsequent starts. I hammered the crap outta it on the way home and zero issues. TCC slip was bang on where I expected, and held tons of power on the last WOT run before I got home.
Am I missing something about their operation? (I hate just throwing parts at a problem without first understanding it. I want to know exactly what's going on inside any of my hardware).
Or.. Are you just giving me the first answer you found on the Googler? I've already been told it's the 3-4 frictions, but so far none of the guys who's said that, has been able to explain why I get perfect shifting most of the time, nor are they able to explain how burnt 3-4 frictions causes the trans to never even attempt to shift to third. As I said, the ECM commands 3rd, but trans stays in second. When ECM commands 4th, THAT's when I get neutral. Everything I've read about burned 3-4 says I should get zero power transfer in 3rd or 4th, but no one ever says anything about the trans not even attempting to shift to 3rd when commanded.
Last edited by Ben Feral Selinger; 10-17-2016 at 10:53 AM.
10-17-2016, 11:14 AM
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Join Date: Oct 2016
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4l60e behind the 5.3 in my frankenrunner (we call it the Choda-Runner). First test drive (street), I was getting a 500rpm flare on 2-3 shift. Dumped in some Lucas transmission fixer snake oil and it cleaned it right up. I chalked it up to bad trans fluid. Shifts are all smooth and grab nice at all RPM.
Took it out last night for it's first test on the trail. About half way through the trail, I went to pop it in reverse and noticed the shifter lever was binding out on the top of the trans a little. Put in reverse, and hit the gas. It bucked like a retard. Try again, same thing. Buddy tells me my reverse lights are flickering, so I figure the trans must have moved up a little and on torque, was causing the shifter cable to stretch and dump it back into park.
No problem. Just hold onto the shifter just right and back up.
On a faster stretch of trail, (in OD on the shifter), I noticed commanded gear was 3rd, but I was clearly in second, and my TCC slip was reading -2600 (engine RPM 2200, in 4L). I didn't know what to think, so just went faster. When trans commanded 4th, I lost all power out the trans. Manually shift it into the 3 position, and it dumps back into 2 and won't even attempt to shift to 3 (ECM commands 3, but clearly never leaves 2).
On the way home I had LOTS of time to test stuff, as it's normally a 40 minute drive but I couldn't get past 2nd gear.
Shift position:
1 - 1st gear start and holds to any RPM.
2 - 2nd gear start and holds.
3 - Normal shift pattern through 1-2, 3 is commanded but never shifts.
4 - Normal shift patter, but never get 3rd, and when we're going fast enough for 4, it finally shifts out of second and then I lose all transmission output power. Like in neutral.
Trans was a touch warm at the time as I hadn't installed a secondary cooler yet. 108C, which really isn't that hot though. I figured at this point that the 3rd accumulator wasn't able to overcome the 2nd piston, which explains why I couldn't get out of 2nd and afaik, the 3rd accumulator is the only common denominator between the 2-3 shift, and having OD available at all, as 3rd accum feeds the 3-4 clutches (right?)
This morning, I hopped in truck to get coffee. Shifter was MUCH smoother. Still binding but nowhere near as bad. First run out the driveway, no 3 or 4. Stop at the light and go again, shifts perfect through all gears. Got all the way to my coffee and home with crisp shifts and OD TCC lockup.
So wtf? My original thought was the 3rd accumulator, mainly because this problem seems clearly a hydraulic one, especially in that it still persisted for the first run of the morning, but went completely away after cycling through the gears once. I can't see how busted 3-4 frictions could cause this. Also, fluid temp is now cold, and thus more viscous. A leaking 3rd accum could potentially work fine when cold, but be unable to overcome the 2nd piston when hot.
BUT, the trans shifted perfectly in all gears, after cycling through a full shift pattern this morning, and this morning the shifter itself isn't binding (much).
Am I on the right track with the 3rd accumulator, or is there any way it's something as simple as my shifter not quite syncing with the detents in the trans?
Took it out last night for it's first test on the trail. About half way through the trail, I went to pop it in reverse and noticed the shifter lever was binding out on the top of the trans a little. Put in reverse, and hit the gas. It bucked like a retard. Try again, same thing. Buddy tells me my reverse lights are flickering, so I figure the trans must have moved up a little and on torque, was causing the shifter cable to stretch and dump it back into park.
No problem. Just hold onto the shifter just right and back up.
On a faster stretch of trail, (in OD on the shifter), I noticed commanded gear was 3rd, but I was clearly in second, and my TCC slip was reading -2600 (engine RPM 2200, in 4L). I didn't know what to think, so just went faster. When trans commanded 4th, I lost all power out the trans. Manually shift it into the 3 position, and it dumps back into 2 and won't even attempt to shift to 3 (ECM commands 3, but clearly never leaves 2).
On the way home I had LOTS of time to test stuff, as it's normally a 40 minute drive but I couldn't get past 2nd gear.
Shift position:
1 - 1st gear start and holds to any RPM.
2 - 2nd gear start and holds.
3 - Normal shift pattern through 1-2, 3 is commanded but never shifts.
4 - Normal shift patter, but never get 3rd, and when we're going fast enough for 4, it finally shifts out of second and then I lose all transmission output power. Like in neutral.
Trans was a touch warm at the time as I hadn't installed a secondary cooler yet. 108C, which really isn't that hot though. I figured at this point that the 3rd accumulator wasn't able to overcome the 2nd piston, which explains why I couldn't get out of 2nd and afaik, the 3rd accumulator is the only common denominator between the 2-3 shift, and having OD available at all, as 3rd accum feeds the 3-4 clutches (right?)
This morning, I hopped in truck to get coffee. Shifter was MUCH smoother. Still binding but nowhere near as bad. First run out the driveway, no 3 or 4. Stop at the light and go again, shifts perfect through all gears. Got all the way to my coffee and home with crisp shifts and OD TCC lockup.
So wtf? My original thought was the 3rd accumulator, mainly because this problem seems clearly a hydraulic one, especially in that it still persisted for the first run of the morning, but went completely away after cycling through the gears once. I can't see how busted 3-4 frictions could cause this. Also, fluid temp is now cold, and thus more viscous. A leaking 3rd accum could potentially work fine when cold, but be unable to overcome the 2nd piston when hot.
BUT, the trans shifted perfectly in all gears, after cycling through a full shift pattern this morning, and this morning the shifter itself isn't binding (much).
Am I on the right track with the 3rd accumulator, or is there any way it's something as simple as my shifter not quite syncing with the detents in the trans?
Sorry if this is ignorant, but why does it shift perfectly though all gears this morning after cycling through all the gears once? From what I understand if the 3-4 clutches, if they're burnt to the point I get no power transmission, they shouldn't grab perfectly now...?
Hell, they shifted perfectly in the donor truck, which is 2000lbs heavier, and had zero problem shifting for the first hour or so on the trail. Just can't wrap my head around how they can work perfectly, and then not at all, and then perfectly again.
Also seems real strange to me that there was zero power transfer coming out of the driveway, but then perfect on all subsequent starts. I hammered the crap outta it on the way home and zero issues. TCC slip was bang on where I expected, and held tons of power on the last WOT run before I got home.
Am I missing something about their operation? (I hate just throwing parts at a problem without first understanding it. I want to know exactly what's going on inside any of my hardware).
Or.. Are you just giving me the first answer you found on the Googler? I've already been told it's the 3-4 frictions, but so far none of the guys who's said that, has been able to explain why I get perfect shifting most of the time, nor are they able to explain how burnt 3-4 frictions causes the trans to never even attempt to shift to third. As I said, the ECM commands 3rd, but trans stays in second. When ECM commands 4th, THAT's when I get neutral. Everything I've read about burned 3-4 says I should get zero power transfer in 3rd or 4th, but no one ever says anything about the trans not even attempting to shift to 3rd when commanded.
Hell, they shifted perfectly in the donor truck, which is 2000lbs heavier, and had zero problem shifting for the first hour or so on the trail. Just can't wrap my head around how they can work perfectly, and then not at all, and then perfectly again.
Also seems real strange to me that there was zero power transfer coming out of the driveway, but then perfect on all subsequent starts. I hammered the crap outta it on the way home and zero issues. TCC slip was bang on where I expected, and held tons of power on the last WOT run before I got home.
Am I missing something about their operation? (I hate just throwing parts at a problem without first understanding it. I want to know exactly what's going on inside any of my hardware).
Or.. Are you just giving me the first answer you found on the Googler? I've already been told it's the 3-4 frictions, but so far none of the guys who's said that, has been able to explain why I get perfect shifting most of the time, nor are they able to explain how burnt 3-4 frictions causes the trans to never even attempt to shift to third. As I said, the ECM commands 3rd, but trans stays in second. When ECM commands 4th, THAT's when I get neutral. Everything I've read about burned 3-4 says I should get zero power transfer in 3rd or 4th, but no one ever says anything about the trans not even attempting to shift to 3rd when commanded.
You have an very aggressive tone, however that could be uncontrolled frustrations with your 4L60e. Your 3/4 clutches able to cycle because you have allowed them to cool down overnight. It's temporary shifting correctly because the metal to metal contact friction remains stable as long as it's cool/cold. The moment your transmission heats up, it's good-bye 3rd gear...it's a phantom shift sir and it will drive you nuts theorizing the probable cause....
However - I will recommend that you check for the (Vehicle Speed Sensor) VSS drop off....it usually happens when you do burnouts "Grabs" or have installed a (Higher Stall Converter). Turn the car off, disconnect the positive battery post for 30 seconds, reconnect.... give it a spin....it the problem goes away...you have VSS Drop off and need to send your computer to someone that can reprogram it for the newly intended use.... if the problem persists...."No 3rd Gear" then you have burned/wore out 3/4 pack of clutches.
I hope this helps..
Eddie
P.s I build transmissions for a living..... I don't have to lean on Google I have 10 years experience.
10-17-2016, 06:41 PM
#5
Moderator
If you are using e.g. HP Tuners or other scanner to confirm that the PCM is commanding 3rd, but the trans stays in 2nd, then you do indeed have a strange problem.
A sticking shift solenoid could cause that - I recall another off-roader who bent the pan and damaged a shift solenoid. The micro-filter on the solenoid can also clog and cause strange symptoms.
A leaking 3rd accumulator would not leave you in 2nd as the hydraulics release the pressure to the 2nd servo piston during the 2->3 shift.
OOPS CORRECTION: In 3rd gear the apply pressure to the 2nd gear servo piston is not released. However since the 3rd gear fluid has more surface area on the servo piston that the 2nd gear fluid, the band is released. See my post #14 for more details.
However, your problems with 3rd and 4th are very strong symptoms of a failed 3/4 clutch.
So, taking EddieGoesFast's comments into account, you may even have multiple problems. And the snake oil is covering up something and confusing us all.
If you really don't want to remove and rebuild the trans now, here are some suggestions that have some chance of fixing your problems and aren't too difficult.
1. Ensure the shift linkage and accurate.
2. Remove the pan and dump the 4-5 quarts that are in it. Examine the fluid for friction material which thickens it.
3. Replace the two shift solenoids.
4. Replace the manifold pressure switch which can cause very strange symptoms.
5. Replace the filter.
6. Install the pan and add 4-5 quarts fluid, aiming to overfill by 1/2 quart.
If that doesn't fix it (probably not), you have at least done all you could and have replaced a few parts that should be replaced as part of a rebuild anyway.
A sticking shift solenoid could cause that - I recall another off-roader who bent the pan and damaged a shift solenoid. The micro-filter on the solenoid can also clog and cause strange symptoms.
A leaking 3rd accumulator would not leave you in 2nd as the hydraulics release the pressure to the 2nd servo piston during the 2->3 shift.
OOPS CORRECTION: In 3rd gear the apply pressure to the 2nd gear servo piston is not released. However since the 3rd gear fluid has more surface area on the servo piston that the 2nd gear fluid, the band is released. See my post #14 for more details.
However, your problems with 3rd and 4th are very strong symptoms of a failed 3/4 clutch.
So, taking EddieGoesFast's comments into account, you may even have multiple problems. And the snake oil is covering up something and confusing us all.
If you really don't want to remove and rebuild the trans now, here are some suggestions that have some chance of fixing your problems and aren't too difficult.
1. Ensure the shift linkage and accurate.
2. Remove the pan and dump the 4-5 quarts that are in it. Examine the fluid for friction material which thickens it.
3. Replace the two shift solenoids.
4. Replace the manifold pressure switch which can cause very strange symptoms.
5. Replace the filter.
6. Install the pan and add 4-5 quarts fluid, aiming to overfill by 1/2 quart.
If that doesn't fix it (probably not), you have at least done all you could and have replaced a few parts that should be replaced as part of a rebuild anyway.
Last edited by mrvedit; 10-19-2016 at 08:37 AM. Reason: Added a correction
10-17-2016, 07:04 PM
#6
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Join Date: Oct 2016
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If you are using e.g. HP Tuners or other scanner to confirm that the PCM is commanding 3rd, but the trans stays in 2nd, then you do indeed have a strange problem.
A sticking shift solenoid could cause that - I recall another off-roader who bent the pan and damaged a shift solenoid. The micro-filter on the solenoid can also clog and cause strange symptoms.
A leaking 3rd accumulator would not leave you in 2nd as the hydraulics release the pressure to the 2nd servo piston during the 2->3 shift.
However, your problems with 3rd and 4th are very strong symptoms of a failed 3/4 clutch.
So, taking EddieGoesFast's comments into account, you may even have multiple problems. And the snake oil is covering up something and confusing us all.
If you really don't want to remove and rebuild the trans now, here are some suggestions that have some chance of fixing your problems and aren't too difficult.
1. Ensure the shift linkage and accurate.
2. Remove the pan and dump the 4-5 quarts that are in it. Examine the fluid for friction material which thickens it.
3. Replace the two shift solenoids.
4. Replace the manifold pressure switch which can cause very strange symptoms.
5. Replace the filter.
6. Install the pan and add 4-5 quarts fluid, aiming to overfill by 1/2 quart.
If that doesn't fix it (probably not), you have at least done all you could and have replaced a few parts that should be replaced as part of a rebuild anyway.
A sticking shift solenoid could cause that - I recall another off-roader who bent the pan and damaged a shift solenoid. The micro-filter on the solenoid can also clog and cause strange symptoms.
A leaking 3rd accumulator would not leave you in 2nd as the hydraulics release the pressure to the 2nd servo piston during the 2->3 shift.
However, your problems with 3rd and 4th are very strong symptoms of a failed 3/4 clutch.
So, taking EddieGoesFast's comments into account, you may even have multiple problems. And the snake oil is covering up something and confusing us all.
If you really don't want to remove and rebuild the trans now, here are some suggestions that have some chance of fixing your problems and aren't too difficult.
1. Ensure the shift linkage and accurate.
2. Remove the pan and dump the 4-5 quarts that are in it. Examine the fluid for friction material which thickens it.
3. Replace the two shift solenoids.
4. Replace the manifold pressure switch which can cause very strange symptoms.
5. Replace the filter.
6. Install the pan and add 4-5 quarts fluid, aiming to overfill by 1/2 quart.
If that doesn't fix it (probably not), you have at least done all you could and have replaced a few parts that should be replaced as part of a rebuild anyway.
Ahem......the Powertrain Control Module activates and deactivates the two shift solenoids in a predetermined pattern so that 4 specific gear ratios can be achieved. They are:
1st Gear: Solenoid 1-2: ON Solenoid 2-3: ON
2st Gear: Solenoid 1-2: OFF Solenoid 2-3: ON
3st Gear: Solenoid 1-2: OFF Solenoid 2-3: OFF
4st Gear: Solenoid 1-2: ON Solenoid 2-3: OFF
When either of these two shift solenoids fail, the PCM commands the transmission to operate in LIMP IN MODE and this means that the transmission will run in 2nd gear ONLY....no 1st and no 3rd or 4th whatsoever. You're obviously not in LIMP MODE because you have more than 2nd gear. Just not 3rd gear......
It's more than snake oil to learn about the operating theory of the 4L60-E transmission...
I would insist that you rebuild the transmission by a qualified reputable transmission company or person.
Eddie
10-17-2016, 10:11 PM
#7
Moderator
Eddie, first, welcome to the ls1tech; I hope you stay active here as we can always use another pro.
While I agree with your conclusion that the 3/4 clutch is likely shot, for many members here rebuilding a trans is a serious financial hit to be avoided if possible or at least delayed as long as possible.
Therefore, I feel that people want me to suggest easy/cheap things to try even if there is only a slim chance that it works. And every once in a while it does work.
Probably a typo on your part, but in most cases limp mode on the 4L60E is with both solenoids OFF, which is 3rd gear.
Here is an old thread where the OP had an intermittent problem where the trans sometimes shifted fine and other times went into limp mode. (Granted different from Ben's problem.)
https://ls1tech.com/forums/automatic...-94-4l60e.html
While I agree with your conclusion that the 3/4 clutch is likely shot, for many members here rebuilding a trans is a serious financial hit to be avoided if possible or at least delayed as long as possible.
Therefore, I feel that people want me to suggest easy/cheap things to try even if there is only a slim chance that it works. And every once in a while it does work.
Probably a typo on your part, but in most cases limp mode on the 4L60E is with both solenoids OFF, which is 3rd gear.
Here is an old thread where the OP had an intermittent problem where the trans sometimes shifted fine and other times went into limp mode. (Granted different from Ben's problem.)
https://ls1tech.com/forums/automatic...-94-4l60e.html
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10-17-2016, 10:51 PM
#8
TECH Fanatic
A mechanically stuck "ON" 2-3 Shift Solenoid can cause these symptoms, Don't rule out wiring issues/shorts keeping the 2-3 SS circuit grounded/low.....Just because the PCM is suppose to throw a code for incorrect voltage........doesn't mean it will 100% of the time.
You can physically monitor Voltage on the 2-3 shift solenoid circuit with a Voltmeter.
High Voltage (@ Battery Voltage)= Solenoid "Off"
Low Voltage= Solenoid "On"
You can physically monitor Voltage on the 2-3 shift solenoid circuit with a Voltmeter.
High Voltage (@ Battery Voltage)= Solenoid "Off"
Low Voltage= Solenoid "On"
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dawnbeaver (06-13-2022)
10-18-2016, 06:51 AM
#9
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Eddie, first, welcome to the ls1tech; I hope you stay active here as we can always use another pro.
While I agree with your conclusion that the 3/4 clutch is likely shot, for many members here rebuilding a trans is a serious financial hit to be avoided if possible or at least delayed as long as possible.
Therefore, I feel that people want me to suggest easy/cheap things to try even if there is only a slim chance that it works. And every once in a while it does work.
Probably a typo on your part, but in most cases limp mode on the 4L60E is with both solenoids OFF, which is 3rd gear.
Here is an old thread where the OP had an intermittent problem where the trans sometimes shifted fine and other times went into limp mode. (Granted different from Ben's problem.)
https://ls1tech.com/forums/automatic...-94-4l60e.html
While I agree with your conclusion that the 3/4 clutch is likely shot, for many members here rebuilding a trans is a serious financial hit to be avoided if possible or at least delayed as long as possible.
Therefore, I feel that people want me to suggest easy/cheap things to try even if there is only a slim chance that it works. And every once in a while it does work.
Probably a typo on your part, but in most cases limp mode on the 4L60E is with both solenoids OFF, which is 3rd gear.
Here is an old thread where the OP had an intermittent problem where the trans sometimes shifted fine and other times went into limp mode. (Granted different from Ben's problem.)
https://ls1tech.com/forums/automatic...-94-4l60e.html
Good Morning!
It's a pleasure to be here and thanks for the warm welcome. I will be here forever or until I don't pay my internet service provider (which ever occurs first).
Eddie
10-18-2016, 11:22 AM
#10
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Eddie, first, welcome to the ls1tech; I hope you stay active here as we can always use another pro.
While I agree with your conclusion that the 3/4 clutch is likely shot, for many members here rebuilding a trans is a serious financial hit to be avoided if possible or at least delayed as long as possible.
Therefore, I feel that people want me to suggest easy/cheap things to try even if there is only a slim chance that it works. And every once in a while it does work.
Probably a typo on your part, but in most cases limp mode on the 4L60E is with both solenoids OFF, which is 3rd gear.
Here is an old thread where the OP had an intermittent problem where the trans sometimes shifted fine and other times went into limp mode. (Granted different from Ben's problem.)
https://ls1tech.com/forums/automatic...-94-4l60e.html
While I agree with your conclusion that the 3/4 clutch is likely shot, for many members here rebuilding a trans is a serious financial hit to be avoided if possible or at least delayed as long as possible.
Therefore, I feel that people want me to suggest easy/cheap things to try even if there is only a slim chance that it works. And every once in a while it does work.
Probably a typo on your part, but in most cases limp mode on the 4L60E is with both solenoids OFF, which is 3rd gear.
Here is an old thread where the OP had an intermittent problem where the trans sometimes shifted fine and other times went into limp mode. (Granted different from Ben's problem.)
https://ls1tech.com/forums/automatic...-94-4l60e.html
If I tell them the trans won't shift out of 2nd, that it holds 2nd, and that the ECM has commanded 3rd, they are always positive it's a hydraulic circuit issue. If however, I say I can't get 3rd or 4th, they immediately jump to 3-4 clutches being bad, even if I explain AFTER, that it's holding 2nd and never goes into 3rd to even try to free spin.
To me, I've just described the exact same symptoms in a slightly different order, but get completely different answers for each.
Looking at the hydraulic circuit diagrams, 2nd is disabled and 3rd is applied by the same circuit (in that sequence). If 2nd cannot be disabled, 3rd definitely cannot be applied, which means the 3-4 clutches aren't even involved yet. Yes, they may not be working, but they aren't supposed to be working yet because 2nd hasn't shut down, and until it does, the 3-4 simply can't even attempt to apply.
Now, once we get to 4th and free spin, it's entirely possible that IS because of burned 3-4 clutches, but I don't see the point in replacing the 3-4 clutches when we KNOW we have a problem upstream causing the 2nd to stay applied. Does that make sense? I'm not arguing that the 3-4 could be pooched. Just that there's no way to know that until 2nd shuts down and the trans tries to grab 3rd.
Looking through the diagrams, I'm seeing at least 5 or 6 circuits required for 3rd to operate correctly, and several of them MUST be working as they're shared with both 1 and 2. So what I'm trying to figure out is which circuits are required to affect the 2-3 shift, as well as to engage 4th (the stuff we know does not work) but are not involved in the 1, 2, or reverse.
According to the service manual, the 2nd apply piston MUST be pushed over into the disabled position, for the fluid to to get to the 3-4 clutch accumulator.
Is this not correct, or am I derping out here and not understanding something? I just don't see how we can be holding 2nd, but blame the 3-4 clutches. If the 2-4 band hasn't released, 3-4 clutches cannot engage (in 3rd).
_______________________
2-4 Band Release and 3-4 Clutch
Accumulation
In Third gear, 3rd accumulator fluid is
routed to the release side of the 2nd apply
piston. The surface area on the release
SERVO ASSEMBLY AND
2-4 BAND
The servo assembly and 2-4
band (602) are located in the
front of the transmission case
and applied in Second and
Fourth gears. In Third gear,
the servo assembly releases
the band and acts as an
accumulator for the 3-4 clutch
apply. The band is held
stationary to the transmission
case by the band anchor pin
(49) and wraps around the
reverse input housing (605).
When compressed by the
servo assembly, the 2-4 band
holds the reverse input
housing stationary to the
transmission case.
side of the 2nd apply piston (17) and
servo cushion spring retainer (15) is
greater than the surface area that 2nd
clutch fluid pressure covers on the apply
side of the piston. Therefore, the force
from 3rd accumulator fluid pressure, in
addition to servo return spring (12) force,
overcomes the force of 2nd clutch fluid
pressure. The 2nd apply piston then
moves the apply pin (13) away from the
2-4 band to release the band from the
reverse input housing.
3rd accumulator fluid is fed by 3-4 clutch
fluid which is used to apply the 3-4
clutch. The movement of the 2nd apply
piston against 2nd clutch fluid pressure
acts as an accumulator to absorb initial 3-
4 clutch apply fluid. This action helps
cushion the 3-4 clutch apply, as well as
release the 2-4 band.
2-4 Band Applied – Fourth Gear
In Fourth gear, 4th fluid is routed through
the center of the apply pin and acts on the
apply side of the 4th apply piston (25).
4th fluid pressure moves the 4th apply
piston (25) and apply pin (13) to apply
the band. The 4th apply piston moves
against the 4th apply spring (22) to help
cushion the band apply in Fourth gear.
10-18-2016, 12:15 PM
#11
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The cost of a rebuild isn't the concern. I just enjoy learning, which you don't do by throwing parts at a problem, and every single transmission guy I've asked has given a different answer depending on how I explain the problem.
If I tell them the trans won't shift out of 2nd, that it holds 2nd, and that the ECM has commanded 3rd, they are always positive it's a hydraulic circuit issue. If however, I say I can't get 3rd or 4th, they immediately jump to 3-4 clutches being bad, even if I explain AFTER, that it's holding 2nd and never goes into 3rd to even try to free spin.
To me, I've just described the exact same symptoms in a slightly different order, but get completely different answers for each.
Looking at the hydraulic circuit diagrams, 2nd is disabled and 3rd is applied by the same circuit (in that sequence). If 2nd cannot be disabled, 3rd definitely cannot be applied, which means the 3-4 clutches aren't even involved yet. Yes, they may not be working, but they aren't supposed to be working yet because 2nd hasn't shut down, and until it does, the 3-4 simply can't even attempt to apply.
Now, once we get to 4th and free spin, it's entirely possible that IS because of burned 3-4 clutches, but I don't see the point in replacing the 3-4 clutches when we KNOW we have a problem upstream causing the 2nd to stay applied. Does that make sense? I'm not arguing that the 3-4 could be pooched. Just that there's no way to know that until 2nd shuts down and the trans tries to grab 3rd.
Looking through the diagrams, I'm seeing at least 5 or 6 circuits required for 3rd to operate correctly, and several of them MUST be working as they're shared with both 1 and 2. So what I'm trying to figure out is which circuits are required to affect the 2-3 shift, as well as to engage 4th (the stuff we know does not work) but are not involved in the 1, 2, or reverse.
According to the service manual, the 2nd apply piston MUST be pushed over into the disabled position, for the fluid to to get to the 3-4 clutch accumulator.
Is this not correct, or am I derping out here and not understanding something? I just don't see how we can be holding 2nd, but blame the 3-4 clutches. If the 2-4 band hasn't released, 3-4 clutches cannot engage (in 3rd).
_______________________
2-4 Band Release and 3-4 Clutch
Accumulation
In Third gear, 3rd accumulator fluid is
routed to the release side of the 2nd apply
piston. The surface area on the release
SERVO ASSEMBLY AND
2-4 BAND
The servo assembly and 2-4
band (602) are located in the
front of the transmission case
and applied in Second and
Fourth gears. In Third gear,
the servo assembly releases
the band and acts as an
accumulator for the 3-4 clutch
apply. The band is held
stationary to the transmission
case by the band anchor pin
(49) and wraps around the
reverse input housing (605).
When compressed by the
servo assembly, the 2-4 band
holds the reverse input
housing stationary to the
transmission case.
side of the 2nd apply piston (17) and
servo cushion spring retainer (15) is
greater than the surface area that 2nd
clutch fluid pressure covers on the apply
side of the piston. Therefore, the force
from 3rd accumulator fluid pressure, in
addition to servo return spring (12) force,
overcomes the force of 2nd clutch fluid
pressure. The 2nd apply piston then
moves the apply pin (13) away from the
2-4 band to release the band from the
reverse input housing.
3rd accumulator fluid is fed by 3-4 clutch
fluid which is used to apply the 3-4
clutch. The movement of the 2nd apply
piston against 2nd clutch fluid pressure
acts as an accumulator to absorb initial 3-
4 clutch apply fluid. This action helps
cushion the 3-4 clutch apply, as well as
release the 2-4 band.
2-4 Band Applied – Fourth Gear
In Fourth gear, 4th fluid is routed through
the center of the apply pin and acts on the
apply side of the 4th apply piston (25).
4th fluid pressure moves the 4th apply
piston (25) and apply pin (13) to apply
the band. The 4th apply piston moves
against the 4th apply spring (22) to help
cushion the band apply in Fourth gear.
If I tell them the trans won't shift out of 2nd, that it holds 2nd, and that the ECM has commanded 3rd, they are always positive it's a hydraulic circuit issue. If however, I say I can't get 3rd or 4th, they immediately jump to 3-4 clutches being bad, even if I explain AFTER, that it's holding 2nd and never goes into 3rd to even try to free spin.
To me, I've just described the exact same symptoms in a slightly different order, but get completely different answers for each.
Looking at the hydraulic circuit diagrams, 2nd is disabled and 3rd is applied by the same circuit (in that sequence). If 2nd cannot be disabled, 3rd definitely cannot be applied, which means the 3-4 clutches aren't even involved yet. Yes, they may not be working, but they aren't supposed to be working yet because 2nd hasn't shut down, and until it does, the 3-4 simply can't even attempt to apply.
Now, once we get to 4th and free spin, it's entirely possible that IS because of burned 3-4 clutches, but I don't see the point in replacing the 3-4 clutches when we KNOW we have a problem upstream causing the 2nd to stay applied. Does that make sense? I'm not arguing that the 3-4 could be pooched. Just that there's no way to know that until 2nd shuts down and the trans tries to grab 3rd.
Looking through the diagrams, I'm seeing at least 5 or 6 circuits required for 3rd to operate correctly, and several of them MUST be working as they're shared with both 1 and 2. So what I'm trying to figure out is which circuits are required to affect the 2-3 shift, as well as to engage 4th (the stuff we know does not work) but are not involved in the 1, 2, or reverse.
According to the service manual, the 2nd apply piston MUST be pushed over into the disabled position, for the fluid to to get to the 3-4 clutch accumulator.
Is this not correct, or am I derping out here and not understanding something? I just don't see how we can be holding 2nd, but blame the 3-4 clutches. If the 2-4 band hasn't released, 3-4 clutches cannot engage (in 3rd).
_______________________
2-4 Band Release and 3-4 Clutch
Accumulation
In Third gear, 3rd accumulator fluid is
routed to the release side of the 2nd apply
piston. The surface area on the release
SERVO ASSEMBLY AND
2-4 BAND
The servo assembly and 2-4
band (602) are located in the
front of the transmission case
and applied in Second and
Fourth gears. In Third gear,
the servo assembly releases
the band and acts as an
accumulator for the 3-4 clutch
apply. The band is held
stationary to the transmission
case by the band anchor pin
(49) and wraps around the
reverse input housing (605).
When compressed by the
servo assembly, the 2-4 band
holds the reverse input
housing stationary to the
transmission case.
side of the 2nd apply piston (17) and
servo cushion spring retainer (15) is
greater than the surface area that 2nd
clutch fluid pressure covers on the apply
side of the piston. Therefore, the force
from 3rd accumulator fluid pressure, in
addition to servo return spring (12) force,
overcomes the force of 2nd clutch fluid
pressure. The 2nd apply piston then
moves the apply pin (13) away from the
2-4 band to release the band from the
reverse input housing.
3rd accumulator fluid is fed by 3-4 clutch
fluid which is used to apply the 3-4
clutch. The movement of the 2nd apply
piston against 2nd clutch fluid pressure
acts as an accumulator to absorb initial 3-
4 clutch apply fluid. This action helps
cushion the 3-4 clutch apply, as well as
release the 2-4 band.
2-4 Band Applied – Fourth Gear
In Fourth gear, 4th fluid is routed through
the center of the apply pin and acts on the
apply side of the 4th apply piston (25).
4th fluid pressure moves the 4th apply
piston (25) and apply pin (13) to apply
the band. The 4th apply piston moves
against the 4th apply spring (22) to help
cushion the band apply in Fourth gear.
Good afternoon,
I'll explain this a different way.... the 3/4 clutch's are the high school dropout's of the 4L60E transmission world. They learned just enough to work, but when challenged they often quit on you when it's their time to prove themselves.
Let's pull the 3/4 clutch pack into the light and expose them for the failures they truly are:
The 3/4 gear is friction applied (4th Gear Requires help from the 2-4 band *Servo) but that's another topic... getting back on topic of the 3/4 clutch pack.
In 4L60E(s) transmission in 3rd gear BOTH shift solenoids are "OFF" and the way the solenoids and electrical circuits are setup, it ABSOLUTELY could not be the solenoids fault because you 1st Gear & 2nd Gear Shift, and you also have reverse. That only leaves the 3/4 Clutch Pack Assembly as the failure.
If you're still not understand what I am saying..... find the fuse for the transmission and remove/pull it out. You should only have 3rd gear (slow movement of the vehicle, remember both shift solenoids are off) if the car/truck doesn't move...... the 3/4 frictions are just metal/burned up and they have exposed themselves, yet, again as utter failures.
Eddie
P.s
and if you really want to learn more about them...nothing is like pulling one apart and tear it open, no better time to do than now.
10-18-2016, 08:36 PM
#12
TECH Fanatic
In 4L60E(s) transmission in 3rd gear BOTH shift solenoids are "OFF" and the way the solenoids and electrical circuits are setup, it ABSOLUTELY could not be the solenoids fault because you 1st Gear & 2nd Gear Shift, and you also have reverse. That only leaves the 3/4 Clutch Pack Assembly as the failure.
When the 3-4's burn down, & the Shift Solenoids & Hydraulics are sound, The trans will shift into 1st gear as the Band gets knocked off by 3rd Accumulator/3rd Clutch Oil, The unit will still have 1st & 2nd......But when the 2-3 shift is commanded the trans will revert mechanically to 1st gear.
A mechanically Stuck "ON" 2-3 Shift Solenoid WILL cause the unit to stay in 2nd when both SS are "OFF" then shift to 1st gear when the 1-2 SS is commanded "ON" for 4th gear.
10-19-2016, 08:19 AM
#13
Moderator
To expand on Clinebarger's "the trans will revert mechanically to 1st gear" - with the shifter in [OD] the overrun clutches are never applied and therefore the pseudo 1st gear does not produce any engine braking - the sprag free-wheels and it feels like neutral.
While a shift solenoid mechanically stuck in the "ON" position is rare, it has been reported here and IIRC one instance was in an off-road vehicle in which the trans pan had dented and bent the solenoid.
Ben: Eddie's suggestion to pull the trans fuse is excellent as this will normally give you only 3rd gear. If the 3/4 clutch is worn out, you will know because the car will never get up to any real speed. Note that the start will be sluggish, but if the 3/4 clutch is OK you should be able to accelerate briskly when you hit 25mph.
Of course if the 2-3 Shift solenoid is stuck in ON, you will start in 2nd gear and remain there. If you know your RPM-MPH ratio you should be able to tell if its 2nd or 3rd.
While a shift solenoid mechanically stuck in the "ON" position is rare, it has been reported here and IIRC one instance was in an off-road vehicle in which the trans pan had dented and bent the solenoid.
Ben: Eddie's suggestion to pull the trans fuse is excellent as this will normally give you only 3rd gear. If the 3/4 clutch is worn out, you will know because the car will never get up to any real speed. Note that the start will be sluggish, but if the 3/4 clutch is OK you should be able to accelerate briskly when you hit 25mph.
Of course if the 2-3 Shift solenoid is stuck in ON, you will start in 2nd gear and remain there. If you know your RPM-MPH ratio you should be able to tell if its 2nd or 3rd.
10-19-2016, 08:32 AM
#14
Moderator
Looking at the hydraulic circuit diagrams, 2nd is disabled and 3rd is applied by the same circuit (in that sequence). If 2nd cannot be disabled, 3rd definitely cannot be applied, which means the 3-4 clutches aren't even involved yet. Yes, they may not be working, but they aren't supposed to be working yet because 2nd hasn't shut down, and until it does, the 3-4 simply can't even attempt to apply....
According to the service manual, the 2nd apply piston MUST be pushed over into the disabled position, for the fluid to to get to the 3-4 clutch accumulator.
Is this not correct, or am I derping out here and not understanding something? I just don't see how we can be holding 2nd, but blame the 3-4 clutches. If the 2-4 band hasn't released, 3-4 clutches cannot engage (in 3rd).
According to the service manual, the 2nd apply piston MUST be pushed over into the disabled position, for the fluid to to get to the 3-4 clutch accumulator.
Is this not correct, or am I derping out here and not understanding something? I just don't see how we can be holding 2nd, but blame the 3-4 clutches. If the 2-4 band hasn't released, 3-4 clutches cannot engage (in 3rd).
Reviewing the hydraulic circuits again for 3rd gear (page 59 of the 4L60-E Technicians Guide), the 2nd gear circuit is APPLIED and there is force on the 2nd gear servo piston. (I earlier stated that 2nd fluid is not applied and I will correct that post.) However since the release side of the 2nd gear servo piston has a much larger surface area that the apply side, the 3rd gear fluid can easily overcome the 2nd apply pressure and release the band.
So the 2nd servo piston does NOT need to move over to let 3rd fluid in - remember in 4th gear that the servo is applied and the 3/4 clutch is engaged. In 4th gear the combination of pressure from both the 4th gear and 2nd gear servo is enough to overcome the pressure from the 3rd apply fluid, and apply the band.
The following users liked this post:
Jdizzle420 (07-26-2024)
09-28-2021, 09:45 AM
#15
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no 3rd Good afternoon,
I'll explain this a different way.... the 3/4 clutch's are the high school dropout's of the 4L60E transmission world. They learned just enough to work, but when challenged they often quit on you when it's their time to prove themselves.
Let's pull the 3/4 clutch pack into the light and expose them for the failures they truly are:
The 3/4 gear is friction applied (4th Gear Requires help from the 2-4 band *Servo) but that's another topic... getting back on topic of the 3/4 clutch pack.
In 4L60E(s) transmission in 3rd gear BOTH shift solenoids are "OFF" and the way the solenoids and electrical circuits are setup, it ABSOLUTELY could not be the solenoids fault because you 1st Gear & 2nd Gear Shift, and you also have reverse. That only leaves the 3/4 Clutch Pack Assembly as the failure.
If you're still not understand what I am saying..... find the fuse for the transmission and remove/pull it out. You should only have 3rd gear (slow movement of the vehicle, remember both shift solenoids are off) if the car/truck doesn't move...... the 3/4 frictions are just metal/burned up and they have exposed themselves, yet, again as utter failures.
Eddie
P.sand if you really want to learn more about them...nothing is like pulling one apart and tear it open, no better time to do than now.
I'll explain this a different way.... the 3/4 clutch's are the high school dropout's of the 4L60E transmission world. They learned just enough to work, but when challenged they often quit on you when it's their time to prove themselves.
Let's pull the 3/4 clutch pack into the light and expose them for the failures they truly are:
The 3/4 gear is friction applied (4th Gear Requires help from the 2-4 band *Servo) but that's another topic... getting back on topic of the 3/4 clutch pack.
In 4L60E(s) transmission in 3rd gear BOTH shift solenoids are "OFF" and the way the solenoids and electrical circuits are setup, it ABSOLUTELY could not be the solenoids fault because you 1st Gear & 2nd Gear Shift, and you also have reverse. That only leaves the 3/4 Clutch Pack Assembly as the failure.
If you're still not understand what I am saying..... find the fuse for the transmission and remove/pull it out. You should only have 3rd gear (slow movement of the vehicle, remember both shift solenoids are off) if the car/truck doesn't move...... the 3/4 frictions are just metal/burned up and they have exposed themselves, yet, again as utter failures.
Eddie
P.s
and if you really want to learn more about them...nothing is like pulling one apart and tear it open, no better time to do than now.
09-28-2021, 10:34 AM
#16
TECH Addict
First off Cdmartin0626 welcome to LS1 Tech.
You would most likely get more help if you started your own thread. Give detailed information of what is going on with your transmission and some back ground info, such as what type of vehicle it is in, year, engine and a little history on what has been done to the trans.
You would most likely get more help if you started your own thread. Give detailed information of what is going on with your transmission and some back ground info, such as what type of vehicle it is in, year, engine and a little history on what has been done to the trans.
09-29-2022, 06:54 PM
#17
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Good afternoon,
I'll explain this a different way.... the 3/4 clutch's are the high school dropout's of the 4L60E transmission world. They learned just enough to work, but when challenged they often quit on you when it's their time to prove themselves.
Let's pull the 3/4 clutch pack into the light and expose them for the failures they truly are:
The 3/4 gear is friction applied (4th Gear Requires help from the 2-4 band *Servo) but that's another topic... getting back on topic of the 3/4 clutch pack.
In 4L60E(s) transmission in 3rd gear BOTH shift solenoids are "OFF" and the way the solenoids and electrical circuits are setup, it ABSOLUTELY could not be the solenoids fault because you 1st Gear & 2nd Gear Shift, and you also have reverse. That only leaves the 3/4 Clutch Pack Assembly as the failure.
If you're still not understand what I am saying..... find the fuse for the transmission and remove/pull it out. You should only have 3rd gear (slow movement of the vehicle, remember both shift solenoids are off) if the car/truck doesn't move...... the 3/4 frictions are just metal/burned up and they have exposed themselves, yet, again as utter failures.
Eddie
P.sand if you really want to learn more about them...nothing is like pulling one apart and tear it open, no better time to do than now.
I'll explain this a different way.... the 3/4 clutch's are the high school dropout's of the 4L60E transmission world. They learned just enough to work, but when challenged they often quit on you when it's their time to prove themselves.
Let's pull the 3/4 clutch pack into the light and expose them for the failures they truly are:
The 3/4 gear is friction applied (4th Gear Requires help from the 2-4 band *Servo) but that's another topic... getting back on topic of the 3/4 clutch pack.
In 4L60E(s) transmission in 3rd gear BOTH shift solenoids are "OFF" and the way the solenoids and electrical circuits are setup, it ABSOLUTELY could not be the solenoids fault because you 1st Gear & 2nd Gear Shift, and you also have reverse. That only leaves the 3/4 Clutch Pack Assembly as the failure.
If you're still not understand what I am saying..... find the fuse for the transmission and remove/pull it out. You should only have 3rd gear (slow movement of the vehicle, remember both shift solenoids are off) if the car/truck doesn't move...... the 3/4 frictions are just metal/burned up and they have exposed themselves, yet, again as utter failures.
Eddie
P.s
and if you really want to learn more about them...nothing is like pulling one apart and tear it open, no better time to do than now.
09-29-2022, 07:26 PM
#18
i've often wonder what possesses someone to spend the time to register on a forum, and then reply to an old thread to someone that hasnt logged in in years. are they being genuinely helpful or just being a virtual know-it-all?
09-29-2022, 07:54 PM
#19
TECH Addict
I'm hoping that it is because they don't know how a forum works. This forum is dying, so I try to help the new people with how these things work. There has been a lot of rudeness in here the last few years. I don't know if that is the reason it is dying or because the LS1/4L60e is becoming an obsolete platform. I'm not saying you were rude tayto, just needed to get on a soapbox for a minute. I really like this forum and hate seeing it die.
Last edited by bbond105; 09-29-2022 at 08:07 PM.
09-29-2022, 09:15 PM
#20
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4l60e behind the 5.3 in my frankenrunner (we call it the Choda-Runner). First test drive (street), I was getting a 500rpm flare on 2-3 shift. Dumped in some Lucas transmission fixer snake oil and it cleaned it right up. I chalked it up to bad trans fluid. Shifts are all smooth and grab nice at all RPM.
Took it out last night for it's first test on the trail. About half way through the trail, I went to pop it in reverse and noticed the shifter lever was binding out on the top of the trans a little. Put in reverse, and hit the gas. It bucked like a retard. Try again, same thing. Buddy tells me my reverse lights are flickering, so I figure the trans must have moved up a little and on torque, was causing the shifter cable to stretch and dump it back into park.
No problem. Just hold onto the shifter just right and back up.
On a faster stretch of trail, (in OD on the shifter), I noticed commanded gear was 3rd, but I was clearly in second, and my TCC slip was reading -2600 (engine RPM 2200, in 4L). I didn't know what to think, so just went faster. When trans commanded 4th, I lost all power out the trans. Manually shift it into the 3 position, and it dumps back into 2 and won't even attempt to shift to 3 (ECM commands 3, but clearly never leaves 2).
On the way home I had LOTS of time to test stuff, as it's normally a 40 minute drive but I couldn't get past 2nd gear.
Shift position:
1 - 1st gear start and holds to any RPM.
2 - 2nd gear start and holds.
3 - Normal shift pattern through 1-2, 3 is commanded but never shifts.
4 - Normal shift patter, but never get 3rd, and when we're going fast enough for 4, it finally shifts out of second and then I lose all transmission output power. Like in neutral.
Trans was a touch warm at the time as I hadn't installed a secondary cooler yet. 108C, which really isn't that hot though. I figured at this point that the 3rd accumulator wasn't able to overcome the 2nd piston, which explains why I couldn't get out of 2nd and afaik, the 3rd accumulator is the only common denominator between the 2-3 shift, and having OD available at all, as 3rd accum feeds the 3-4 clutches (right?)
This morning, I hopped in truck to get coffee. Shifter was MUCH smoother. Still binding but nowhere near as bad. First run out the driveway, no 3 or 4. Stop at the light and go again, shifts perfect through all gears. Got all the way to my coffee and home with crisp shifts and OD TCC lockup.
So wtf? My original thought was the 3rd accumulator, mainly because this problem seems clearly a hydraulic one, especially in that it still persisted for the first run of the morning, but went completely away after cycling through the gears once. I can't see how busted 3-4 frictions could cause this. Also, fluid temp is now cold, and thus more viscous. A leaking 3rd accum could potentially work fine when cold, but be unable to overcome the 2nd piston when hot.
BUT, the trans shifted perfectly in all gears, after cycling through a full shift pattern this morning, and this morning the shifter itself isn't binding (much).
Am I on the right track with the 3rd accumulator, or is there any way it's something as simple as my shifter not quite syncing with the detents in the trans?
Took it out last night for it's first test on the trail. About half way through the trail, I went to pop it in reverse and noticed the shifter lever was binding out on the top of the trans a little. Put in reverse, and hit the gas. It bucked like a retard. Try again, same thing. Buddy tells me my reverse lights are flickering, so I figure the trans must have moved up a little and on torque, was causing the shifter cable to stretch and dump it back into park.
No problem. Just hold onto the shifter just right and back up.
On a faster stretch of trail, (in OD on the shifter), I noticed commanded gear was 3rd, but I was clearly in second, and my TCC slip was reading -2600 (engine RPM 2200, in 4L). I didn't know what to think, so just went faster. When trans commanded 4th, I lost all power out the trans. Manually shift it into the 3 position, and it dumps back into 2 and won't even attempt to shift to 3 (ECM commands 3, but clearly never leaves 2).
On the way home I had LOTS of time to test stuff, as it's normally a 40 minute drive but I couldn't get past 2nd gear.
Shift position:
1 - 1st gear start and holds to any RPM.
2 - 2nd gear start and holds.
3 - Normal shift pattern through 1-2, 3 is commanded but never shifts.
4 - Normal shift patter, but never get 3rd, and when we're going fast enough for 4, it finally shifts out of second and then I lose all transmission output power. Like in neutral.
Trans was a touch warm at the time as I hadn't installed a secondary cooler yet. 108C, which really isn't that hot though. I figured at this point that the 3rd accumulator wasn't able to overcome the 2nd piston, which explains why I couldn't get out of 2nd and afaik, the 3rd accumulator is the only common denominator between the 2-3 shift, and having OD available at all, as 3rd accum feeds the 3-4 clutches (right?)
This morning, I hopped in truck to get coffee. Shifter was MUCH smoother. Still binding but nowhere near as bad. First run out the driveway, no 3 or 4. Stop at the light and go again, shifts perfect through all gears. Got all the way to my coffee and home with crisp shifts and OD TCC lockup.
So wtf? My original thought was the 3rd accumulator, mainly because this problem seems clearly a hydraulic one, especially in that it still persisted for the first run of the morning, but went completely away after cycling through the gears once. I can't see how busted 3-4 frictions could cause this. Also, fluid temp is now cold, and thus more viscous. A leaking 3rd accum could potentially work fine when cold, but be unable to overcome the 2nd piston when hot.
BUT, the trans shifted perfectly in all gears, after cycling through a full shift pattern this morning, and this morning the shifter itself isn't binding (much).
Am I on the right track with the 3rd accumulator, or is there any way it's something as simple as my shifter not quite syncing with the detents in the trans?