I know there are several posts out there with different opinions. I'd love to know the latest opinion on what people use for the Evo 9 MR transmission fluid, the 6 speed.
the car currently runs on the OEM Diaqueen and shifting is somewhat fine but not as smooth as I'd like, especially at high rpms it gets harder to shift
4th gear mostly "clicks" or grinds into gear and very rarely it'll shift smoothly and sometimes at high rpm 3rd gear will grind and I've hit 6th once 2 years ago, was never able to after that lol.
The car is pretty much just cammed by previous owner with an intake system to kinda know the power on the car, not much overstock
thanks in advance 🙂

 

I used Redline MT90, now Redline 75w90NS

 

i did this except i started on mt85. switched to NS since it shares fluid with the front diff.

re: the OP, honestly it sounds like the trans is gonna need a rebuild soon

 

Eventually gonna have to replace the synchros but before all that becomes mandatory I just wanna try a different tranny oil. I've heard some good things about AMSOIL syncheomesh and recently read on BG Synchroshift II transmission fluid
​​Are you guys mixing the oils with OEM or draining with new oil?
I just don't want to destroy the trans, a little paranoid with some things I've read
I've had the car for about 4 years, never changed tranny fluid, it's driven daily but not far, I've put about 28k miles on it since I got it

 

i flush annually due to the sensitivity of the trans. not amsoil. mt85, mt90, or 75w90ns. that's kept my 6spd healthy through a lot of abuse.

 

Awesome, I'll try out the Redline MT90
Thanks for all your help!

 

drain it, hopefully your gear oil is still there and isnt milky yet

 

The gear oil I've changed once and boy was it terrible gross black definitely milky at the time, that was over a year ago
How many quarts would I need for the tranny and gear oils? I know I can check owners Manuel but easier to ask here

 

here you go.
https://www.evolutionm.net/forums/ev...uantities.html

 

Ty sir

 

Now I'm being difficult
MT85 or MT90 for Evo 9 MR tranny?
I live in Southern California

 

MT90. I've used both multiple times and MT90 always shifted better, I think the MT85 is too thin. I have a 6 speed too btw. Im probably going to change to the 75w90NS next though for the added benefit of GL-5 over GL-4

 

I would say MT90 is "good enough" but not good enough for track racing. TRE's minimum rec for his new builds is 75w90NS but highly recommends 75w140NS

 

there's some power dependency too. i'm not really making more than 360whp so the stress is considerably less than someone making, say 500whp

 

Would the 'NS' version be needed for an USDM 05 RS evo?