1972 Build thread.

[hemi43]

Originally Posted by kehstr

Is this on a differential with some sort of locker?

Yes ! I've had issues with both Auburn style (cones) and clutch style that come in our Blazers when using synthetics. I'm not a chemist, but I assume it has something to do with the friction modifiers much like the difference between Dextron and F type transmission fluid.

On my Blazer, I used Amsoil synthetic in the transfer case as well as the front Diff, but because the front is just an open diff, I had no issues.

What's odd, is that it claims right on the Amsoil tech sheet that their oil is compatible with locking differentials.