View Full Version : T56 fluid change time

04-04-2005, 06:37 PM
:burnout: Getting ready to drop my trans fluid after 28K mi and I see three popular

Dexron III (Stock trans fluid)
GM Synchromesh (GM recommended T-56 transmissions)
Mobile 1 ATF (Aftermarket high performance ATF)

From what I read here, lots of people prefer Mobil 1 or
GM Synchromesh fluid over stock Dexron III ATF fluid.

My concern is that GM fluid does not appear to be an ATF and
thus can not stand up to high temperature as well as ATF types.
Here in the Arizona, with summer temperatures of 110F+ :mad: ... thats hot.

I've also heard that Mobile 1 ATF offers smoother shifting ?

So, in conclusion, my only question is whether Mobile 1 offers any improved protection and shifting improvements over Dexon III fluid ??

Any comments from Mobile 1 or GM Sychromesh users ?

04-04-2005, 08:05 PM
Currently using Mobil 1 and it seems to do well, better than stock fluid. Getting ready to change to Amsoil.

04-05-2005, 08:14 AM
gonna swap to GM Syncromesh pretty soon...a few friends have switched to it and said it got rid of some of the noise in the trans