Tranny issues
09-18-2012, 06:08 PM
#1
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Tranny issues I have a 95 z28 with a built 4l60e tranny and a 2500 stall.
The coil pack died yesterday, car would not start. Had it brought to my shop, replaced the coil today and car fired right up. went to drive the car home and all seemed ok, stopped at a light and when the light turned green i hit the gas and the car did nothing but rev up to 24-2800rpm then it felt like i was on the brakes. so i took it easy the rest of the way home. Once i was in my drive way i floored the car and the same thing felt like i was on the brakes.Now i have never had a tranny issue ever with this tranny since the rebuild. i jacked up the car and the calipers are not stuck at all. jack up the rear and the tires spin as soon as you release the brake.
So what i am asking is this related too my coil issue like i left a ground off or something? or is it possible the tow truck guy messed it up somehow?
the fluid is perfect and does not smell burnt or have any glitter in it that i could tell.
The coil pack died yesterday, car would not start. Had it brought to my shop, replaced the coil today and car fired right up. went to drive the car home and all seemed ok, stopped at a light and when the light turned green i hit the gas and the car did nothing but rev up to 24-2800rpm then it felt like i was on the brakes. so i took it easy the rest of the way home. Once i was in my drive way i floored the car and the same thing felt like i was on the brakes.Now i have never had a tranny issue ever with this tranny since the rebuild. i jacked up the car and the calipers are not stuck at all. jack up the rear and the tires spin as soon as you release the brake.
So what i am asking is this related too my coil issue like i left a ground off or something? or is it possible the tow truck guy messed it up somehow?
the fluid is perfect and does not smell burnt or have any glitter in it that i could tell.
09-18-2012, 10:54 PM
#2
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Was it towed with the rear wheels on the ground?
If yes, how far?
This would turn the transmission internals without oil pressure.
Perhaps someone here knows if this would cause damage.
If yes, how far?
This would turn the transmission internals without oil pressure.
Perhaps someone here knows if this would cause damage.
09-18-2012, 11:33 PM
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Yes it will damage the transmission, towing the car with rear wheels on the ground if the engine is not running.
I know this from bad experience :-(
Posted from LS1Tech.com App for Android
I know this from bad experience :-(
Posted from LS1Tech.com App for Android
09-19-2012, 06:02 AM
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Im sure a flat bed towed it. But i was thinking maybe he pulled it up the bed in gear or something. Not sure if that would hurt it. Then they moved it in the yard but the rear wheels were on the claws. Just pisses me off.
09-19-2012, 04:52 PM
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ok the tow had nothing to do with it, it just bad luck i guess.
I did find out that the car does this more when your in over drive or 3rd gear vs 2nd gear.
when its in 2nd gear its not so bad
3rd gear its like i have a 3000k stall and im holding the brakes
over drive is the same as 3rd gear.
is this a sign the tranny is going out or is the valve body the issue?
Its not the brakes!!!!!
and the car will only rev up to 3200rpm when its in those 2 gears.
I did find out that the car does this more when your in over drive or 3rd gear vs 2nd gear.
when its in 2nd gear its not so bad
3rd gear its like i have a 3000k stall and im holding the brakes
over drive is the same as 3rd gear.
is this a sign the tranny is going out or is the valve body the issue?
Its not the brakes!!!!!
and the car will only rev up to 3200rpm when its in those 2 gears.
09-19-2012, 05:55 PM
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This sounds like the forward sprag is slipping.
The forward sprag supplies all of the forward thrust in [D] and [OD] (or [3] and [D] depending on your shifter's numbering scheme).
In [1] and [2], the "overrun clutch" is also engaged and supplies forward thrust in addition to the sprag.
Note that the overrun clutch is weak, as its primary purpose is to provide engine braking when you downshift, e.g. downhill in the mountains. Therefore anything over maybe 25% throttle will damage the overrun clutch when the sprag has failed.
Replacing the forward sprag requires transmission removal and moderate amount of disassembly. Considering the age of your trans and that the sprag may have shredded metal all over the trans, it is time for a complete rebuild.
I'm no expert, so seek other advice too.
The forward sprag supplies all of the forward thrust in [D] and [OD] (or [3] and [D] depending on your shifter's numbering scheme).
In [1] and [2], the "overrun clutch" is also engaged and supplies forward thrust in addition to the sprag.
Note that the overrun clutch is weak, as its primary purpose is to provide engine braking when you downshift, e.g. downhill in the mountains. Therefore anything over maybe 25% throttle will damage the overrun clutch when the sprag has failed.
Replacing the forward sprag requires transmission removal and moderate amount of disassembly. Considering the age of your trans and that the sprag may have shredded metal all over the trans, it is time for a complete rebuild.
I'm no expert, so seek other advice too.
09-20-2012, 05:44 PM
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I was thinking the problem was more of a 1-2 shift solenoid causing the car to start in 4th gear rather than 1st, giving the car the feeling of the brakes dragging. Yet if you shift the car into 1st or 2nd manually the car seems fine, then shift into over drive to lock up the converter.
I was asking to see what people would say or suggest to prove a point to one of my Technitions. Its much easier to suggest a failed part then to ask more questions and get all the information you can before suggesting a failed part right away.
I was asking to see what people would say or suggest to prove a point to one of my Technitions. Its much easier to suggest a failed part then to ask more questions and get all the information you can before suggesting a failed part right away.
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09-20-2012, 08:01 PM
#8
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A failed shift solenoid (burnt out or shorted) will generally produce a "Check engine" light. Guess that should always be the first question.
Your idea of a failed shift solenoid is valid; it could be clogged and therefore not give a Check-engine light. Technically a failure of solenoid B could cause the car to start in 4th instead of 1st, a failure of solenoid A could cause the car to start in 2nd.
Jack up the car again, put it in [D4] and check the speedometer speed at idle and compare it to the speed in [D1] and [D2]. That should help you determine what gear the trans is in when in [D4].
Your idea of a failed shift solenoid is valid; it could be clogged and therefore not give a Check-engine light. Technically a failure of solenoid B could cause the car to start in 4th instead of 1st, a failure of solenoid A could cause the car to start in 2nd.
Jack up the car again, put it in [D4] and check the speedometer speed at idle and compare it to the speed in [D1] and [D2]. That should help you determine what gear the trans is in when in [D4].
