I just took the diff apart and it still had most of the fluid I had put in previously. To experiment I put in some HPI diff grease and buttoned everything up again.

On this test run, the problem wasn't as pronounced as before on the throttle, but it was still there. It was especially noticable when braking hard. The left rear tire would lockup but the right would continue to roll. This would cause it to swing left during breaking.

This is going to make driving it in the dirt tricky.

ben