I'm tired of searching the forum and coming up short. I need to know for sure what transmission is in thing. It's an 09 lnf with lsd. Is it a F35 or a MU3? I wanna change to Redline synthetic tranny oil. On their wbsite they recommend D4 ATF for the MU3 (the only option tranny). But for an 05-07 SS with the same MU3 tranny, recommends using MTL which is a thicker weight oil. I am so confused. What makes these 2 trannys take 2 different oils with the same code #?

 

the mu3 and f35 are the same tranny, just different names (f35 is the type, mu3 is the rpo code). the only real difference between the sc and tc version is the final drive ratio.

as for oil, do not use ATF in this transmission, is far too thin. i recently change the fluid in my 05 sc and the oil from gm was gl4 manual trans fluid, and iirc it was 75w85 on the bottle. gm did change the oil between the sc and tc, im not sure why, likely to allow for quicker shifting with the no lift shift feature. myself, id stick with the factory fluid. im a transmission builder, ive used many different aftermarket fluids in different applications and the best thing for a manual trans is to use the factory fluid.

 

Wow thanks a lot man. Too bad I already bought 2 quarts. I always do my research after I buy things.

 

your from canada A?
(my canadian friend hates that lol)

 

ehhhh man lol, yeah i would stick to stock fluide