Well, the BJ8 is about done, but..... On a short drive Friday, a knocking began from the rear axle area. I checked wheel and hub tightness, as well as drive shaft and universal joints, and exhaust. With the car on jack stands and no wheels, and in gear with engine running, the knocking is evident, and related to speed. The wheels will turn through maybe 5-10 degrees of rotation before the driveshaft begins to turn. I'm thinking that something is awry in the differential, possibly a broken tooth on the pinion gear. I can pull it out and get it to a pro, but before I do that, I just wondered if there might be another diagnostic approach before major surgery. Thanks.