Very good info. I think I'm going to try this in my transmission, just found a local shop that carries it.

 

Interestingly though, the shop called their BG rep and they are recommending 75W-80 for my car. I'm kind of ify about that...

Update:
I called BG directly. They told me that the Synchro Shift II comes in 75W-80 ONLY. The one that's 75W-90 is the Ultraguard. So, are you sure you got Synchro Shift II in 75W90? Anyway to verify?

 

^^ Sorry you are correct. It was 75w80 Synchro Shift II

 

Wow... I just realized that I have driven 30k miles in the last year. I will be doing this service again within the next 10k miles and will certainly use the same fluids.

 

Thanks for the info OP. Roughly how often should trans/diff oil be changed? Mine was changed about 12k ago. I know it should still be good, but I get rough shifts sometimes mainly when my tranny is cold from 1st to 2nd. I will be flushing my clutch fluids soon, and im thinking about doing the tranny/diff as well.

 

Figured I would bump this up since it's about time for me to service the transmission and differential again. I will be using the same fluids once again. My sedan is on the cusp of 150k miles now.