Help with 4l80e final assembly
Thread Starter
Teching In
Joined: Dec 2019
Posts: 37
Likes: 2
From: Md
i checked the pump i have and there is no rattle from the pressure regulator springs. they are seated as i described. do you get the noise on every start up or only if it's been sitting a while? also when you were checking your input and output clearances, it is normal as mentioned earlier to hear a squeak type noise when turning the output shaft in one direction. that rotation usually needs assistance from a channel lock or vise grip unless your hands are made like that!! easy to turn in opposite direction. as for the input shaft there should be a good amount of resistance turning in either direction using your hands only. if either shaft did not react in this manner, there is something not seated correctly and/or incorrect clearances in the unit. i know you have a lot of time invested into this unit, but if you can't solve 100% of your issues with the trans installed, i would take a deep breath, pull it again and start from scratch, rechecking every aspect of the assembly. i have saved on my computer the ATSG manual for 4l80. i'll send that to you tomorrow. it's a pretty large pdf.
Thread Starter
Teching In
Joined: Dec 2019
Posts: 37
Likes: 2
From: Md
i checked the pump i have and there is no rattle from the pressure regulator springs. they are seated as i described. do you get the noise on every start up or only if it's been sitting a while? also when you were checking your input and output clearances, it is normal as mentioned earlier to hear a squeak type noise when turning the output shaft in one direction. that rotation usually needs assistance from a channel lock or vise grip unless your hands are made like that!! easy to turn in opposite direction. as for the input shaft there should be a good amount of resistance turning in either direction using your hands only. if either shaft did not react in this manner, there is something not seated correctly and/or incorrect clearances in the unit. i know you have a lot of time invested into this unit, but if you can't solve 100% of your issues with the trans installed, i would take a deep breath, pull it again and start from scratch, rechecking every aspect of the assembly. i have saved on my computer the ATSG manual for 4l80. i'll send that to you tomorrow. it's a pretty large pdf.
Staging Lane
Joined: Mar 2023
Posts: 61
Likes: 10
From: Connecticut
when i'm checking input and output shaft rotation i have the transmission in a horizontal position with everything installed and torqued except the valve body. clockwise rotation of the output shaft should require some effort using a channel lock or similar and you are ok hearing a squawking type noise but it should feel smooth. counter clockwise rotation should require less effort and also feel smooth with no unusual noises. it is possible though to hear cutch rotation noise. you should be able to rotate the input shaft in either direction by hand feeling some resistance but still a smooth feel. there is too much weight on the gear train when trying to rotate the output shaft in a horizontal position. output rollerized should not be a concern as long as you still have some clearance.
Thread Starter
Teching In
Joined: Dec 2019
Posts: 37
Likes: 2
From: Md
Ok I will definitely pay attention to that when I get it back together. So it turns out I had the overdrive sprag set so the rollers were just past the ramps instead of on the ramps so it definitely wasn’t holding. I’m praying that’s gonna solve it bc everything else looks great!
One other concern I had was because I’m using the rollerized Sonnax forward hub it was supposed to really reduce front end play but i still had to use the second thickest selectable stator washer and it’s still like .015 of front play I also used the thickest thrust under the forward hub. I can’t figure out where the slop could come from. Rear end play is .007”. Also can anyone verify for me that when using the rollerized forward hub there should be zero play between the forward hub and direct drum? Thanks
One other concern I had was because I’m using the rollerized Sonnax forward hub it was supposed to really reduce front end play but i still had to use the second thickest selectable stator washer and it’s still like .015 of front play I also used the thickest thrust under the forward hub. I can’t figure out where the slop could come from. Rear end play is .007”. Also can anyone verify for me that when using the rollerized forward hub there should be zero play between the forward hub and direct drum? Thanks
Staging Lane
Joined: Mar 2023
Posts: 61
Likes: 10
From: Connecticut
i was just thinking that i may be wrong on what direction of rotation you would hear the squawking type noise. it might make that noise in the counter clockwise direction. anyhow that noise should only happen in one direction of rotation.
Staging Lane
Joined: Mar 2023
Posts: 61
Likes: 10
From: Connecticut
are you measuring front end play at the input shaft after assembly using a dial indicator and pushing the output shaft forward? before i install the pump i use a h gauge and a feeler gauge to get 12 to 13 thousandths clearance measuring between the h gauge and the selective washer. i have been using this process for years when applicable with no ill effects. i'm pretty sure when checking end play after assembly you might see more clearance since as i said earlier there is a few thousandths of play when pulling up on the input shaft before the whole assembly moves up/forward. i would think that 15 thousandths shouldn't be an issue just as long you are confident in your upgrades. i always mic up replacement washers/bearings to the originals to see if the measurements are identical or real,real close. a little on the loose side is better than to tight.
Correct, clockwise is harder to turn than counter clockwise especially if the unit has fluid on the frictions.
Thread Starter
Teching In
Joined: Dec 2019
Posts: 37
Likes: 2
From: Md
are you measuring front end play at the input shaft after assembly using a dial indicator and pushing the output shaft forward? before i install the pump i use a h gauge and a feeler gauge to get 12 to 13 thousandths clearance measuring between the h gauge and the selective washer. i have been using this process for years when applicable with no ill effects. i'm pretty sure when checking end play after assembly you might see more clearance since as i said earlier there is a few thousandths of play when pulling up on the input shaft before the whole assembly moves up/forward. i would think that 15 thousandths shouldn't be an issue just as long you are confident in your upgrades. i always mic up replacement washers/bearings to the originals to see if the measurements are identical or real,real close. a little on the loose side is better than to tight.
1. my overrun clutch clearance is now around .084” after replacing the frictions and steels. It was sloppy before but this seems excessive. What are the options here? I see no thicker steels or frictions available
2. The aforementioned gap between the input shaft snap ring and overdrive carrier is .090”. This seems way bigger than anything else I’ve seen online. Can this be an issue? It’s an ATI Vasco shaft
thanks
Staging Lane
Joined: Mar 2023
Posts: 61
Likes: 10
From: Connecticut
the spec for the over running clutch is .035 to .095 checking between the pressure plate and snap ring. if you have the old clutches and they're not toast , measure the total stack height compared to the new ones. if the height is slightly smaller than the new ones, you're ok. the snap ring. are you talking about the one the holds the input shaft to the over running planet? if so that snap ring has very little clearance, just enough to spin the snap around the shaft when installed. if the over running planet, carrier and input shaft are assembled correctly, before installing the pump, pulling up slightly on the input shaft you feel full engagement of the planet into the carrier. release the input shaft and you should feel it drop back down. this is normal. we're only talking a few thousandths of movement.
Thread Starter
Teching In
Joined: Dec 2019
Posts: 37
Likes: 2
From: Md
Ok well I finally got a chance to get it back together and it seems pretty damn good except for a few issues. Thanks to everyone who has helped me along the way, I've learned a ton about 4l80's!
-So the 1-2 shift is pretty harsh. I did delete the accumulators this time but was conservative when I drilled the plate. Which would be the best option? Reinstall the accumulators or put in a stock plate and leave 1-2 hole factory or is there a better option?
-I drove the hell out of it last weekend and reverse was all good until sunday afternoon I noticed reverse wouldnt engage until I gave it a little gas. It will move backwards a couple inches then I feel it engage. Seems much better when trans is cold. any ideas?
thank you
-So the 1-2 shift is pretty harsh. I did delete the accumulators this time but was conservative when I drilled the plate. Which would be the best option? Reinstall the accumulators or put in a stock plate and leave 1-2 hole factory or is there a better option?
-I drove the hell out of it last weekend and reverse was all good until sunday afternoon I noticed reverse wouldnt engage until I gave it a little gas. It will move backwards a couple inches then I feel it engage. Seems much better when trans is cold. any ideas?
thank you
What did you do exactly when you say you deleted the 1-2 accumulator? Removed the seals from the piston under the rear servo cover and plugged the hole? What valve body is on it?
What checkballs are omitted?
What is the 1-2 hole currently drilled to in the separator plate? If its a 97+ a new separator plate can be had for cheap off rockauto. If 91-96, you can get the transgo sep plate.
Also what is the stall speed? A larger stall will mask the harshness of the shifts.
What is the travel on the reverse servo pin?
What is your intermediate clutch pack clearance? How many frictions? Wave plate in the intermediate still?
What's pressure reading in reverse?
Seal on reverse servo piston good? Rear servo gasket good? Rear servo cover sanded before installing?
What checkballs are omitted?
What is the 1-2 hole currently drilled to in the separator plate? If its a 97+ a new separator plate can be had for cheap off rockauto. If 91-96, you can get the transgo sep plate.
Also what is the stall speed? A larger stall will mask the harshness of the shifts.
What is the travel on the reverse servo pin?
What is your intermediate clutch pack clearance? How many frictions? Wave plate in the intermediate still?
What's pressure reading in reverse?
Seal on reverse servo piston good? Rear servo gasket good? Rear servo cover sanded before installing?
Last edited by 5.7stroker; Jul 12, 2023 at 05:24 PM.
TECH Junkie
Joined: Jun 2008
Posts: 3,194
Likes: 1,377
From: Nitro Alley
Deleting the 2nd Accumulator can create a can of worms!
Why exactly did you do this?
Do You have a Valve-Body that requires it?
Otherwise, I would go back to having an active 2nd Accumulator.
Why exactly did you do this?
Do You have a Valve-Body that requires it?
Otherwise, I would go back to having an active 2nd Accumulator.
Had a guy that I built a 4L80E for tell me that the car wouldn't move when car was in manual 1 from a starting position. He described the issue as "when you are in manual 2 and drop into manual 1 the transmission locks up" So here I am thinking that I had missed putting on the 1-2 accumulator seals. Since he didn't comment on 3rd or 4th being bad, limp mode didn't cross my mind. He takes it to his mechanic that installed the unit and the guy tells me "false alarm, the fan fuse blew and the trans controller put the car in limp mode because it got too hot. Controller has a safety shutoff on it." This was an Fitech controller he had on it. I know they get a bad rap and everyone says go with US Shift, but it saved him. Everything is working great now.
Last edited by 5.7stroker; Jul 12, 2023 at 08:42 PM.
TECH Enthusiast
Joined: Jan 2019
Posts: 677
Likes: 490
From: Roxana, IL
Ok well I finally got a chance to get it back together and it seems pretty damn good except for a few issues. Thanks to everyone who has helped me along the way, I've learned a ton about 4l80's!
-So the 1-2 shift is pretty harsh. I did delete the accumulators this time but was conservative when I drilled the plate. Which would be the best option? Reinstall the accumulators or put in a stock plate and leave 1-2 hole factory or is there a better option?
-I drove the hell out of it last weekend and reverse was all good until sunday afternoon I noticed reverse wouldnt engage until I gave it a little gas. It will move backwards a couple inches then I feel it engage. Seems much better when trans is cold. any ideas?
thank you
-So the 1-2 shift is pretty harsh. I did delete the accumulators this time but was conservative when I drilled the plate. Which would be the best option? Reinstall the accumulators or put in a stock plate and leave 1-2 hole factory or is there a better option?
-I drove the hell out of it last weekend and reverse was all good until sunday afternoon I noticed reverse wouldnt engage until I gave it a little gas. It will move backwards a couple inches then I feel it engage. Seems much better when trans is cold. any ideas?
thank you
Because the 1-2 accumulator is in the reverse servo I would first look to a missing #2 check-ball or a stuck/missing spring in the accumulator valve in the valve body. I enclosed a 4L80E accumulator function file.
Thread Starter
Teching In
Joined: Dec 2019
Posts: 37
Likes: 2
From: Md
What did you do exactly when you say you deleted the 1-2 accumulator? Removed the seals from the piston under the rear servo cover and plugged the hole? What valve body is on it?
What checkballs are omitted?
What is the 1-2 hole currently drilled to in the separator plate? If its a 97+ a new separator plate can be had for cheap off rockauto. If 91-96, you can get the transgo sep plate.
Also what is the stall speed? A larger stall will mask the harshness of the shifts.
What is the travel on the reverse servo pin?
What is your intermediate clutch pack clearance? How many frictions? Wave plate in the intermediate still?
What's pressure reading in reverse?
Seal on reverse servo piston good? Rear servo gasket good? Rear servo cover sanded before installing?
What checkballs are omitted?
What is the 1-2 hole currently drilled to in the separator plate? If its a 97+ a new separator plate can be had for cheap off rockauto. If 91-96, you can get the transgo sep plate.
Also what is the stall speed? A larger stall will mask the harshness of the shifts.
What is the travel on the reverse servo pin?
What is your intermediate clutch pack clearance? How many frictions? Wave plate in the intermediate still?
What's pressure reading in reverse?
Seal on reverse servo piston good? Rear servo gasket good? Rear servo cover sanded before installing?
So the reverse issue is gone for now and its been engaging fine so I'm table that for now.
Sooo I think I got confused and it was the 3-4 accumulator I deleted which I think is a common mod? basically I got the CK master recal kit with the accumulator delete plate and followed their instructions
Valve body is a new reman sonnax with the overrun clutch valve installed
I believe I left off the #5 and #6 check *****
1-2 I drilled to 0.093" I think but I should be there later today to confirm
Converter, not sure. FTI would never tell me the specs but I would say around 2800-3200rpm
I will get back on the intermediate clearances but they were a tad loose, wave plate in place
thanks
