Whats the best fluid to run in my t5 and also my rear end? Thanks

 

What ever spec fluid your owners manual says to use. Your choose on synthetic vs conventional.

 

Lots of guys tout GM sychromesh for T5s... Mine is full of Mobil 1 synthetic ATF.

My diff is also full of Mobil 1 gear oil (I can't recall the weight off the top of my head 90w140?)... I also threw in some friction modifier just to play it safe with the LSD.

 

dextron iii/mercon for tranny and 75w/90 with one bottle of friction modifier for rear

 

Thanks for the correction!