4L80E Rebuild Question
First is regarding part 659, the output carrier thrust washer that goes between the reaction carrier assembly and the output carrier assembly. My rebuild kit came with a black one (instead of off-white) that is slightly wider. The rebuild kit also came with two bronze output shaft thrust washers that also fit in place of the output carrier thrust washer. Should I go ahead and use the black one, or would the bronze one be a better solution? I am rollerizing the output shaft if that matters. I have around 0.007" end play.
Second question is that the ATSG manual shows part 645 reaction drum spacer ring, looks like a big snap ring in the pictures. But I don't see one in my trans. In the GM Powertrain 4L80E manual it does not show this part. Does my year trans not have this part?
Top row: Stock and new plastic output carrier thrust washer
Bottom row: Stock and new bronze output shaft thrust washers
Thicknesses are written on them in thousandths


Stock output carrier thrust washer:

Stock output shaft thrust washer:
Last edited by Ferocity02; Sep 27, 2013 at 12:33 AM.
And from what little info I found it sounds like part 645 reaction drum spacer ring was eliminated in later models and they went with a low roller clutch that has little "feet" to get the spacing correct. Sound right?
Last edited by Ferocity02; Sep 27, 2013 at 02:02 PM.
I'm curious to which thrust washer I should use, metal or plastic. I am not rollerizing this because it takes some machining to do so and I read that it weakens the assembly.
Where did you read it weakens the assembly and are you making 2000+ HP?
When we use an aftermarket gearset such as a 2.10 or other ratio in high end builds, guess what, it has the bearing between them. These are for 1000+ HP applications and these gearsets are out there at over 3000 HP. Are you really believing some BS on the internet that machining .060" is going to be an issue in your application.?
I got the rear section installed and am having a slight issue. Once I torque down the center support bolt to 32 ft-lbs the main shaft no longer wants to spin freely inside the sun gear shaft. Most of the rotation it will spin freely and then it will get tough spot and it is hard to turn, but I can power through the tough spot and then it will spin freely again again the next turn. Seems like something isn't straight. I'm thinking it's the sun gear shaft bushings that got messed up when I replaced them. They were a bit tighter than the originals, I had to hone them out slightly to get the sun gear shaft over the main shaft. The original bushings even had high spots of abnormal wear.
Is this a concern? I'm thinking of replacing the bushings and trying again.
Is this a concern? I'm thinking of replacing the bushings and trying again.


