Clickety, Clickety, Clickety Rear Axles

The sound is the same when one is using a ratchet to tighten a fastener. The ratchet makes that clicking noise on the return stroke.

The sound is the same on both axles. Using a stethoscope pressed on the backing plates, I can hear the sound. When I replace the drums and turn the axles, the slight noise of the drums rubbing a little on the brake shoes is enough to drown out the clicking. I don't hear anything behind the differential cover.

I checked the gear lube level in the differential, it's not all the way up to the threads of the inspection hole, but it's down maybe half-inch or so.