Cybernetic Medic

I have read some of the posts on changing the fluid in the MN6 trans to improve shifting. Is there any consensus on which is the best... Royal Purple, Amsoil, Redline or just the stock fluid changed more often? Is there any downside to changing it, i.e. voiding the warranty etc.?

I know it's a common problem and a trait of these transmissions but I'm disappointed the way my recently acquired 07 shifts.

drivinfast

Depending on the use there is an issue with the bushings holding the shifter bracket down.

Also there are at least 5 aftermarket shifters

Disappointed how? do you miss 3rd or 5th? mushy?

REVAK

I have had good results with royal purple sycromax for the trans oil. I also recommend the mgw shifter and frequent clutch fluid changes. [search the ranger method, it works ]

Robls6

RPM filled my brand new Level V trans with O'Reilly parts store regular Dextron ATF and said that is all I should use. That's all I needed to hear.

Hoonose

I put Redline into my early '05 this year without any notable effect or improvement.

Cybernetic Medic

The same problems that others have. Notchy shift to 2nd, reluctance to go into 1st or reverse when cold, and a general stiff feeling to shifts.

By comparison, my old 91 Srealth with 185k on it shifts like butter. I know from that car that the trans fluid can make a big difference.

timd38

I use Redline with an MGW shifter and am happy.

slvr06z51

RP SyncroMax made a world of difference. Then added a MGW shifter a week after that. Finally got the desired shift feel that I thought a Vette should have from the day it rolled off the assembly line.

-Nick

Cybernetic Medic

Pretty hard to argue with that... If there was an advantage to using one of the other ATF's out there you would think they would endorse it.

c6_rob

Using royal purple here, happy camper

oneblackvette

carlrx7

im running the old amsoil atf in mine ,, its ok. i think they should send me a case of the new stuff and ill send by this case of old crap! lol

GOLD72

That was also my experience with Redline D4-ATF that I put into my 01Z06 at ~20k. Then again I haven't seen SOTP improvement using AMSOIL ATF in my 06Z06 either.

NormWild

Most are better than the factory fluid, and most people will have not tried multiple fluids to give you any reliable comparison. It will be more of whether people are fans of a particular brand. I figured you can't go wrong with Amsoil, so that is what I used.

C4RACER

Friend of mine runs a performance vette and camaro shop in NC. The recommendation he got from an actual Tremec engineer was to run only Mobil1 ATF, which could very well also be the factory fill.

C2C6Z06

Royal Purple made a big difference on the notchy 1-2 shift issue for me....SOLD!

lsbrodsky

Been lots of threads on this over the years. I went with Royal Purple and love it. Already had an MGW shifter. Also an 07.
Larry

JRHAWK9

RP Syncromax here also, although in colder temps we get here in early Spring and Fall I still do have issues with the 1-2 shift until the car gets warmed up.

Bandit1

AMSOIL. Talk to "Subdriver". He'll hook you up.

JoesC5

I drained the factory fill from my 09 Z06 and replaced with the RP Syncromax and drove it. It was way worse then the factory fill. Drained it, and replaced with Mobil1 ATF and it appeared to be about the same as the factory fill, maybe a tad better. I've put around 5,000 miles on the car since the fluid change and it's a little better shifting 1-2 & 2-3 but I'm still not happy having to granny shift to keep the nibbles/grinds in check. I get my 56 down off the lift every once and awhile and am surprised how well it shifts(1970 Muncie 4 speed/Hurst shifter). It's stiffer shifting then the Z06's transmission but goes into gear with no syncro nibbles/grinds.