I posted this question under the performance forums and got really no responses. I was thinking about changing the tranny fluid to synthetic, but many people have posted and said that they get grinding. And when they change back to regular it goes away. The dealer is no help, they just say that it's up to me. All I want to know is, how many of you have changed their fluid to synthetic and had the grinding, and how many of you have not had grinding? I want to see what the majority is before I change it. Thanks!

 

i wouldnt recommend going from sythetic to regular anything.
that being said, oem tranny fluid is valvolline dyno oil which can be bought at any kragens.

 

We have had a lot of discussion on a lot of different synthetics used in the WRX transmission, with a lot of mixed reviews.

http://www.clubwrx.net/forums/showth...hlight=mobil+1

http://www.clubwrx.net/forums/showth...hlight=mobil+1

dorifto88 is correct, Subaru uses Valvoline 90wt. in both the transmission and the rear diff.

I am running Redline Lightweight Shockproof in both my trans and rear diff. Car shifts a lot smoother right now, but I have been told that this stuff doesn't last for very long. Maybe like 10k miles.

Kurlee Daddee
(THE ORIGINAL)

 

I don't want to know what kind of synthetic to use, I just want to know how many of you had grinding when you put synethic in.

 

I understand that. If you read both links above, there are a few people on those posts that used Mobil 1, had good results for a few months, and then the grinding began.

I have had my Redline synthetic in my car for about a month with no grinding yet.(knocks on wood)

Kurlee Daddee
(THE ORIGINAL)

 

Cool, thanks!