I own a 06 Evo IX MR and I'm at 26000 so the tranny fluid change is coming up in 4000. In the manual, the 6 Speed says only use 75W-85 while the 5 Speed for the Base IX and RS can accept 75W-85 or 75W-90. I was wondering if anybody has used 75W-90 in the 6 Speed MR tranny, and if so, have you seen any negative effects? I'm wondering because the only fluid I can find in 75W-85 is the Diaqueen which is hard to get and fairly expensive, as opposed to the readily available 75W-90, which can be purchased from most companies for a relatively low price. Can I use 75W-90 or must I ABSOLUTELY use 75W-85 in this tranny?

 

you ABSOLUTELY MUST use 75W-85 or you can kiss your tranny bye bye

www.mitsubishiparts.net has fair pricing on the fluid (60-70 bucks I believe)

and for the xcase and rear diff make sure you get the proper lsd gear oil (also available on www.mitsubishiparts.net)

http://www.mitsubishiparts.net/catalog/?section=575 - this is a direct link to both items (130 bucks and you are set)