My new (to me) '99 ext cab 4 cyl 5 sp truck with locking rear diff. has a rumble in the rear. It was evident on straight road, acceleration and deceleration, especially up to about 40 mph, then it becomes less evident. I lifted it up and ran it to listen to the rear end. The wheel bearings sounded silent. The noise came from the diff. The drivers side axle has a sort of catch as it gets rotated.
We removed the 3rd member and put it in a vise. There was a small metal "thing" stuck to the magnetic plug. It looks like a piece of metal from the bottom of a drilled hole - sort of like an egg shell, about 5/16" diameter, and NOT all chewed up. The drivers side output (where the axle engages with the diff) has the "bump" or whatever, evident by putting your fingers in where the axle fits, and rotating the spider gear assy. The "bump" is more noticeable if you also push the spider gear assy in from the passenger side, while rotating the driver side.
The ring and pinion gear look and feel great.
My buddies and I are hesitant to tear down the diff. as we don't have some of the tools called for, and have never done one before. We're trying to decide if I would be better off taking the 3rd member to the local Toyota shop or just buy a new/rebuilt/used 3rd member and be done with things.
I've searched this forum, but haven't come across this particular complaint. Any ideas or suggestions?
Thanks very much. Paul Underwood