4T60-e Shift Kit Write-Up

First off- I give major credit to 3400-95-Modified on 60*v6 for helping me w/ this


A shift kit firms and quickens a shift.

I did mine by shimming the accumulator springs.

In the 4T60-e, you have two choices of accumulator housings, a "4AFW" and a "4CMW". The "4AFW" housing will look like the "second design" (this is the one I have in my GP) and the "4CMW" will look like the "third design". You can find out which design you have by looking at your tranny tag on the back of the trans on the diff housing.








I looked at several 4T60-e's in a local J/Y and the 4AFW looked to be pretty common.

Now, even though the accum housings and pistons look different, I am going to assume that the pistons will all be the same shape and size when taken apart.


I shimmed my 1-2 springs and the 2-3 springs w/ a 3/8" thick bushing (which I made at work), I measured the inside of the pistons and you can see them on the following pics. You won't need to make/get a bushing like I had, a few washers spaced to your wanted thickness will do the trick.

you just need a washer with an outer diameter of 1.5" and a inside diameter of .625". as to how thick the washers are spaced will determine how hard the shift will be. I would recommend making the 1-2 shift bushing thinner that what I have it. I'd go with around a 1/4" thick. Mine is a little too firm, my next fluid change, I will change it out for a thinner bushing. But, I would highly recommend staying with the 3/8" bushing for the 2-3 shift, it works great, not stiff, but quick.









Here are some pics w/ the accum pistons w/ the bushings sitting in them.

the 2-3 piston is thicker than the 1-2 piston on the 4AFW accum housing design.



1-2
without



With





2-3
without


with






here are all the internals laying apart with each set of springs sitting next to its respective piston.







here is the housing in the trans.







to get the housing out of the trans, just release the 4 bolts show here




then gently rotate it down and then side to side to release the tubes out of the housing....don't break them.




once out, just pop the 7mm (IIRC) bolts out of the top of the housing and take it off.

put the bushings in the correct places in the pistons...use "shim 2" that I have labeled here.....the bushings must go there.








there is a small chance that a spring could break....Mine were not broke, and a local trans shop said they have never had broken accum springs, but 3400-95-modified said he has seen them break.

here are the spring part numbers for a 4AFW housing

1-2 outer, 8682700
1-2 inner, 8668631
2-3 outer, 8668487
2-3 inner, 8681456



replace the top of the accum housing a put back in trans like you took out.

you will need to add ~ another quart of trans fluid to replace what was lost from the inside of the accum housing.



here is a vid of the shifts right after I was done.

http://www.youtube.com/watch?v=rt3SNEOd1Zg

I'll update this if I need to. Or if any questions come up.

Edit for Promotion to Article (Robby1870)

I'm combining these first two posts to help in creation of the article:

here is the inside of the accum lid







here is looking down into the accum housing






here is the 1-2 piston in the bottom of the housing w/ the shim in it