4l60e 2-3 slipping shift

[immortality]

I'd try and flush as much out as possible.

I normally drain the pan, clean and fill, then I drop the cooler line after the cooler and aim that at a drain pan and pump out about 4 litres of fluid, that should get plenty out of the converter. Then seal it up and top it up.

[vscapricetim]

Roger that

[vscapricetim]

Dont wanna start and argument but a mineral or synthetic in dex 3? Haha

[immortality]

Dex III should be a mineral based fluid. Dex 6 is the newer GM spec synthetic fluid for their fancy 6,7,8,10 speed transmissions.

The dex III synthetic equivalent is probably something like this (same Dextron IIIH specification as mineral DXIII)

https://penriteoil.com.au/products/atf-fs-full-syn

https://penriteoil.com.au/assets/pis_pd ... neral).pdf
https://penriteoil.com.au/assets/pis_pd ... 0Syn.).pdf

(I use Penrite products so I might be biased).

Ultimately, the 4L60e was designed to use DexIII fluid

[vscapricetim]

Thanks for that immortality

[immortality]

3rd gear in these transmissions really is a bit of a basket case. If you have time for a little light reading,

https://www.sonnax.com/tech_resources/6 ... confidence

Thanks for that immortality

No problem. I've been helping someone else with this exact issue so it has reminded me to do more research.

[delcowizzid]

Possibly may fix it

Screenshot_20240925_003618_Chrome.jpg

[immortality]

Not to expensive either. Just need to pull the trans out.

[immortality]

If you are interested, this guy does a lot of video's explaining how transmissions work in great detail.

https://www.youtube.com/@SouthpawAutoworks

[vscapricetim]

Problem is I'm not even revving that high....