synthetic trans fluid??????

Don't use synthetic gear oil. It's to slippery and the syncros won't work and you will get lots of gear crunch, been there and did that!

If you want to use a synthetic lubricant use one specifically designed for manual transmissions. Redline, Amzoil and Royal Purple all make synthetic manual tranny fluids.

I have running Penzoil Syncromesh fluid in my A833OD, this is not synthetic though. A huge improvement over gear oil in the ease and smoothness of the shifting and a very noticable improvement over the ATF that cam in the tranny.