Does anybody know what kind of Oil does GM use in the SS tranny? In my old Eagle talon TSI changing the oil to GM syncromesh made for a night and day difference on the shifting.

I think I read somewhere it uses Dexron III.

Dextron III is Automatic Transmission Fluid. Manual transmissions use heavy weight gear oil. Every GM 5 speed car I've owned used GM Synchromesh, which I'm assuming is what is still used in the Cobalts

Shouldn't that be in the owners manual? Then again it seems that auto manufacturers have been making the manuals less and less helpful and more of covering their @$$ for driver stupidity.

the newer transmissions use light weight oil in them now , alot of it had to do with cold shifiting issues


the new fluid is a light weight syn oil

The Manual tranny in the 2.2 and 2.4L use dexron 3 and the manual tranny in the 2.0L uses GM part#21018899, only description is manual tranny fluid.

I have a research request in at Redline Oil about what product to use when replacing our MTF. The guy I spoke to was looking into it. I had Redline MTL in my last car and it is great stuff! I'll post back with any news.

The fluid the ss tranny takes is 80w-90 rear oil. You can look in the back of your owners manaul too, it does say the type and how much. :mad: :mad: :mad:

The Manual tranny in the 2.2 and 2.4L use dexron 3 and the manual tranny in the 2.0L uses GM part#21018899, only description is manual tranny fluid.


You are right that the 2.0 uses a specific part#. It is already sythetic fluid that GM has been using for awhile. Replacing it will not give any benefits.