Diaqueen a mineral oil. Breaks down faster and lubrication is inferior to a synthetic.

Amsoil full synthetic. Last longer, lubrication is always there for thr tranny when most needed under high loads and high heat

 

I did oem but going to try amsoil next time heard good things

 

Any one know what shep says to run in his stage one trans?

 

My guess is Redline cause thats what he sells

 

I follow this

http://www.teamrip.com/manual_transm...tion_info.html

 

This wasn't on that list, has anybody used this before?http://www.streettunedmotorsports.co...box_100099.htm

 

There is more to a manual transmission fluid than just how good/long lasting the fluid is (synthetic). Find me a synthetic that shifts as good as the OEM fluid and I'll be interested. (and I'm not talking about in -25 deg weather when the fluid isn't warmed up... under normal conditions, find me a synthetic that beats OEM). Synchros need the right kind of fluid to operate properly. Many things just don't cut it there, or are too slick.

I don't have experience wth the 6 speed, but for the 5.. Diaqueen is the best I've found and I've tried several different things and combinations. MT-90 is the best synthetic I've found, but the shift quality of OEM fluid is the best. It was the same with the STI 6 speed I put in my wrx, oem Subaru Extra-S could not be beat. From what I've read the 6 speed in the evo's is no different. Same with the rear diff, run mitsu lsd oil unless you have an aftermarket rear diff that specifies something else.

 

Thats why i asked what shep says to run i ran a coocktail of two different red-lines in my car now and i feel it is not shifting as smooth as what was in it before

 

I've had good luck with 2 quarts of diaqueen and 1 quart of mt-90. You could probably substitute the redline for another quality synthetic gear oil as well. Helps in cold weather and may provide some of the benefits of synthetic while still retaining the shift quality of oem fluid. But I have no reason to believe the oem fluid is not quality/long life. This isn't just coming from me/my limited experiance- I'm good friends with Jack/Kevin from Jack's transmissions and they have tried everything.

And built trannies still use basically oem parts, so the fluid choice/requirements are not really going to change.

And even if the $20/quart oem fluid has to be changed more often, so be it- I think it's worth it for the shift quality.

But that's my opinion, others may have found different results.

 

Good feedback...

 

Your experience is very oposite than what I had... i had a GSR IX 5speed of course and the diaqueen was not working for me under cold weather I mean 50-70 degrees this is cold for us here in Florida.. it was not working for my fast shifting habits either.... i had a friend that was the master mechanic at mistu and he swapped the fluid for the 6spd tranny fluid... no good either.. i was frustrated found amsoil and switched to them what a night and day difference even when I switched stock clutch to the ACT clutch which are known for no sifting right my tranny was smoth.

 

...well I would expect the AMSOIL dealer to have good results with AMSOIL

Nothing against AMSOIL... I've used it for years in many applications. There are also several other quality oil brands that are every bit as good and in some cases better.

Anyway I am giving an unbiased opinion... I don't get anything out of people using OEM fluid. But my own experience favors it, and the guys who build these transmissions and have done more testing than you can imagine also recommend it.

Hey if it works, run it. Seriously, I'm not telling people not to run AMSOIL, about the only thing I would caution people not to run is synchromesh... but to anyone who is not happy with the way their trans shifts, don't assume you have to run an aftermarket fluid, this is one of those places where the fluid designed to work in your trans... actually works well.

 

I just switched from straight Redline MT-90 to the cocktail, 2 Quarts Redline MT-90 + 1 Quart of Redline MTL (on Advice from Moore Automotive) and my shifting seems much improved. All the notchiness and grind that happened occasionally with straight MT-90 is completely gone in the past 2 days of driving around town. Effing brilliant. Seems like the solution for me.