4L60E Information Thread (Includes 4L65E/4L70E)

[NickTransmissions]

Bumping this thread up with a new video on measuring servo travel/adjusting band clearance in 700R4s and 4L60Es....This vid is one of a two-part series and focuses on GM factory servo and hardware. PT2 will focus on aftermarket servo set ups (Coming soon).

 

[NickTransmissions]

Bumping this thread with a new video on 700R4 and 4L60E Forward Drum Repair...The most common pattern failure, by far, is the 3-4 clutch pack burning up...The primary reason for this in my view, is leaks developing at the base of the input shaft where it's pressed into the drum...Over time, milage, stresses and other factors combine to weaken the drum to the point it's no longer making a perfect seal at the 2-3 feed circuit and fluid begins to leak into the case under high pressures when it should be going directly to the 3rd clutch piston to apply and hold the 3-4 clutch pack...When this starts happening, 3-4 clutch failure isn't far behind.

I show a potential repair procedure using Loctite retaining compound, that if ultimately proves itself to work under operating temperatures, will be a viable option for those looking to repair drum assemblies with mild to moderate leaking in lieu of replacing the drum.

 

[Echo]

I have a question @NickTransmissions

If my drum assemblies appear to be installed correctly (1/4 in below the pump resting surface), and the reverse drum is fully interlocked to the sunshell, should the reverse drum rest on the thrust bearing between the drum assemblies?

When I put the reverse drum onto the input drum, it seats onto the thrust bearing. However, when I put the drum assembly into the case, with the reverse drum properly interlocked to the sun shell, it seems to raise the reverse drum off of the thrust bearing by maybe an 1/8th inch. I'm assuming this is normal, but I'm leaving nothing to chance after the last 2 trauma builds I went through.

NOTE: The sun shell does not have the 4 square cut holes for the washer tabs, so I left the washer out.

EDIT: For clarification, it is a 2004 4L65E with all manner of upgrades (Transgo HD2 Kit, reinforced sun shell, 5 pinion planetary gears, corvette servo, sonnax boost valve, Hi-Per Blue Pistons, and some other stuff I can't rightly remember atm.)

 

[Sam Harris]

Hey @NickTransmissions,
Hope you’re doing well. I really appreciate all your expertise, and sharing your knowledge with the rest of us!
I’m collecting the tools and things I need to swap my transmission, after an apparent forward sprag breakage. (This is what Performabuilt believes is the problem). The Alldatadiy manual suggests I need the tool:
J 21366 Converter Holding Strap
I’ve only found this tool a couple places online and it’s priced between $150-200+, and seems like a pretty basic metal strap. I was hoping you might have a suggestion or, ideally, a cheaper version of this tool you can suggest, which will get the job done. I searched this thread, but didn’t find a tools list. (This would be a great addition imho, but maybe I missed it)
Please let me know your thoughts when you have a moment.

 

[NickTransmissions]

Hey @NickTransmissions,
Hope you’re doing well. I really appreciate all your expertise, and sharing your knowledge with the rest of us!
I’m collecting the tools and things I need to swap my transmission, after an apparent forward sprag breakage. (This is what Performabuilt believes is the problem). The Alldatadiy manual suggests I need the tool:
J 21366 Converter Holding Strap
I’ve only found this tool a couple places online and it’s priced between $150-200+, and seems like a pretty basic metal strap. I was hoping you might have a suggestion or, ideally, a cheaper version of this tool you can suggest, which will get the job done. I searched this thread, but didn’t find a tools list. (This would be a great addition imho, but maybe I missed it)
Please let me know your thoughts when you have a moment.

Hey Sam, you dont need any converter holding strap for any task, just a tool to align the pump halves when you go to reassemble it, assuming you're going to attempt the repair yourself. I can put a list of special tools into this thread sometime soon...

 

[Sam Harris]

Hey Sam, you dont need any converter holding strap for any task, just a tool to align the pump halves when you go to reassemble it, assuming you're going to attempt the repair yourself. I can put a list of special tools into this thread sometime soon...

Thank you for the advice. I’ll be pulling the trans and shipping from Texas to Pennsylvania.. having the folks who built it fix the problem. Good thing I kept my original.. hoping I don’t blow it up before I get this one back.. and I would like to build the original one of these days. The manual says it’s to avoid any damage to the pump if I recall correctly, but if you say I don’t need it, that’s good enough for me. I’ll be doing this on jackstands, so will be as gentle as possible.

 

[NickTransmissions]

Bumping this thread up with another 4L60E video. This one focuses on all the tools, supplies and equipment you'll want to have on hand to rebuild 700R4 and 4L60E transmissions...A great resource for anyone strongly thinking to take on this job!

Enjoy and TIA for watching!

 

[Tataocb]

I have a question on interchangeability of separator plates for 99-2008 transmissions going behind LS engines. I know the early ones should be matched to the paper gasket that show a V/C, and newer ones to the ones showing VB/CA. My question is not about finding the right gasket but mainly if you can use a VB/CA plate (with its corresponding gaskets) with an early valve body, that originally came with a V/C separator plate and vice versa? Or do you need to respect the separator plate/valve body combination?

What about the Transgo 46-96 separator plate? Can it be used to replace both V/C and VB/CA separator plates? I noticed it does not have the additional hole that the newer ones have close to the area where you see the VB/CA markings on the gasket once installed. So it looks more like an early type separator plate in that respect.
I have also seen a couple with the screen integrated to the plate (as opposed to using the filters) with a 1HA inscription on it. I believe those are for 2007-2008 transmissions. Can those be used with older transmissions? The difference I saw when compared to 2000-2006 plates was an additional rectangular hole right next to where the larger screen goes.

 

[NickTransmissions]

I have a question on interchangeability of separator plates for 99-2008 transmissions going behind LS engines. I know the early ones should be matched to the paper gasket that show a V/C, and newer ones to the ones showing VB/CA. My question is not about finding the right gasket but mainly if you can use a VB/CA plate (with its corresponding gaskets) with an early valve body, that originally came with a V/C separator plate and vice versa? Or do you need to respect the separator plate/valve body combination?

What about the Transgo 46-96 separator plate? Can it be used to replace both V/C and VB/CA separator plates? I noticed it does not have the additional hole that the newer ones have close to the area where you see the VB/CA markings on the gasket once installed. So it looks more like an early type separator plate in that respect.
I have also seen a couple with the screen integrated to the plate (as opposed to using the filters) with a 1HA inscription on it. I believe those are for 2007-2008 transmissions. Can those be used with older transmissions? The difference I saw when compared to 2000-2006 plates was an additional rectangular hole right next to where the larger screen goes.

The 46-96 will work on all 4L60E variants from model year 1996-2006; otherwise use early w/early and late with late when it comes to factory plates. There are some subtle differences in the orifices between the Transgo plate and some of the factory plates made for that time frame but they aren't important and won't impact functionality. The 2007+ bonded spacer plates (gaskets are bonded to the plate) are not interchangeable with the earlier models that took the non-bonded gaskets. 2009+ spacer plates are also materially different than 2007-2008 plates; I get all the bonded spacer plates from the dealer.

 

[Tataocb]

Hey @NickTransmissions - I am looking for your help again.

I rebuilt a transmission for a guy with new frictions, seals, gaskets, molded pistons, aluminum accumulator pistons, band, Transgo boost valve. The guy bought a 3000 stall converter from a well known local shop and did the installation. He added 12 qts of fluid. On the initial test drive he felt it slip and added one more quart. The following day, he drove it to work (40 min drive about 30 miles) and noticed that anytime he tried to downshift on the highway, like when trying to merge or pass a car, the transmission acted like it went to neutral, like when 3rd and 4th gear are gone. He also noticed Reverse was not working and the car would move forward in neutral.

He brought it back and I opened it back up and noticed that the topmost sealing ring on the input shaft was completely torn. It was the sealing ring that separates the forward clutch feed hole on the input shaft from essentially where the reverse input drum feed holes would be for reverse. Perhaps it was damaged when I installed the pump, but it still passed the air check with the test plate on the valve body area. I thought I would find one of the forward frictions welded to a steel, but that was not the case. The overrun frictions were not flat, but kind of concave. I replaced all the frictions and sealing rings on the input shaft and gave it back to him.

He installed it again and now the issue with reverse was resolved at first, but eventually it sort of came back where now it he needs to rev it a bit to get it to engage and once it does it feels as if the brakes were applied. The downshift issue is still there. It will still just rev up as if in neutral when he tries to downshift to merge or pass on the freeway. He sent me a video where he is going at 60 mph and when he steps on the accelerator (like to merge or pass another car) it just revs up. If he keeps driving it regularly (just cruising) then it will work fine. That leads me to believe that it is not an issue with the 3/4 clutch pack because if it were burnt up, then he would not be able to accelerate up to 60 mph and cruise at that speed. He sent me another video later where at partial throttle (cruising type driving) he can get it up to 75 MPH and I can see it shift all the way up to 4th gear. He hooked up a scanner and the ECU is commanding 2nd gear when it slips and just revs up.

Could it be something like the 3-2 downshift solenoid or the manifold pressure solenoid? I reused them since this was a low buck rebuild he was trying to get. I installed a corvette servo with a new band and the band engagement tested fine with the test plate. Could it be that the band is not catching the reverse input drum for some reason causing it to go into 1st gear? Maybe I missed something inside the stator where the sealing rings ride?

As always, thanks for sharing your knowledge and all your help. Any insight you can provide would be appreciated.