I'm swapping in a tranny this weekend and I'm going to replace the tranny fluid with GM Synchromesh -- the question is do you mix it with anything else? as in 1qrt synchromesh/2 quarts redline (DCs need 2.3 quarts?) because I've read both. Nobodys explained why.

And I know I need the 'Friction Modified' version. The FM stuff comes in the normal oil container shape vs cylinder for the normal, right?

Thanks

 

gm synchromesh (same as pennzoil synchromesh) and a little better gm synchro. friction modified.
yeah the friction modified stuff comes in a different container than the regular synchro. they also sell a friction modifier in a smaller bottle

I dont think there is a need to go mixing stuff unless needed by differentials

 

from my former home in the Subaru camp, mixing tranny fluids was a HUGE discussion. the reason being that ppl were looking for a mix that was good for the differential as well as the tranny synchros. many found that a using ALL Mobil 1 syn or ALL synchromesh yielded good initial results but after a bit tranny issues like grinding/etc reappeared. conclusion was that the synchromesh was TOO slick, which was great for dif but not for synchros; there wasn't enough friction to spin up the synchros properly (resulting in grinds, etc). a good number of users found good results with about a third synchromesh and the remaining fluid std MTF.

if your tranny is currently performing fine, i would not personally go to an all synchromesh fill. i would do 25-33% synchromesh and the rest standard Honda MTF or comparable.

 

remember that not all trannys require the same grade oil.
synchromesh is around 30 weight wich is what honda recommends.
for personal experience i have been using synchromesh for over 50-60k miles now. tranny's shift like new

 

thanks for explaining, ill take that into consideration