Does anyone know what transmission fluid to use for an 08 cobalt SS. i called gm and they only gave me a part number and the stuff they have is 28$ a QT. any ideas of alternate fluids. and what type of LSD additive do u use as well

 

No LSD additive, get the GM fluid if you can, it's special, trust me. The shop that did mine put in LSJ fluid and it wouldn't sync worth **** and the gears felt sticky.

It's GL-4 fluid, Castrol Syntrans according to Maven, I couldn't find any when I needed it, mixed up a blend of Red Line MT-90 and MTL about 2:1 to get the proper viscosity. Feels/drives close to stock fluid. Our trannies hold 1.8 qt., prob 1.5 on a refill.

If your dealer can get the LNF stuff, get it.

DO NOT put GL-5 or 5+ fluid in our trannies, our LSD doesn't need it and it will be too slippery for our syncros. I have a fluid thread in Drivetrain if you want to read the debate.

https://www.cobaltss.net/forums/drivetrain-79/any-subs-yet-lnf-f35-tranny-fluid-209495/

 

Royal Purple max gear 75w 90 = The best stuff out there and meets all reqiurments

 

Go ahead and use it but it's not going to like it, trust us, get the GM fluid.

 

Everybody says that the GM fluid is a pain in the ass to get because some dealers dont have it and blah blah blah

 

it cost me 26 a quart for the gm **** when I did my clutch

but it is specific to the lnf

 

If I'm not mistaken the GM stuff is meant specifically for the No Lift Shift. I would Stick with the factory stuff.

 

Yep, anything slicker like RP Maxgear which is a GL-5 won't let the syncros engage fast enough for a NLS 'cause it's too slickery. You'll see what I mean if you try it.

GMPD will sell you (as will GM) 6 qts, which is why most dealers won't order/stock it. They don't want the 4 other qts. sittin' on the shelf unless it's a large dealer. They know they won't sell it.

CED would prob ship you 2 though, call Tom.