I have a '74 2000 GTV and it has a clunk in the drivetrain. I thought it was a universal joint - sounds a bit like someone tapping the driveshaft with a hammer. The driveshaft is now rebuilt and the clunk remains. Have traced it to the rear axle and it seems to be related to takeup in the diff. It has a limited slip diff and someone has suggested its normal - anyone know more about diff clunks in LSDs?