Hey I'm doing my own 30k service I'm changing my motor oil w/ mobil1 5/30
and buying oem fuel filter, oil filter, and crush washer. But as for my tranny and frnt & rear diff. what is the BEST oil brand and wieght I can use. I dont race the car too much but do drive hard once in a while. As for radiator I will use 1 or 2 water weters but what anti freez do I use. should I buy the subaru one or something eles. what? thanks for the help

 

Mobil1 isn't the best motor oil. Amsoil is a much better oil as it is a true full-synthetic, Mobil1 isn't. Mobil1 still uses petroleum, while Amsoil is fully man-made.

 

i use castrol gtx 5w30

 

its called search oil, i hear its the best.

 

Personally, I'd run 10/30 Mobil 1 unless you plan on going to Alaska.

Regular 80/90 valvoline in the tranny and diff is fine, since that's what the synchros and limited slip are designed for.

To avoid corrosion, make sure you use an equal portion of distilled water and subaru or honda antifreeze/anti-boil, and add one Subaru cooling system conditioner (stop-leak)... they started recommending this as some WRXs develop minor coolant seepage at the head gasket and/or radiator tanks.