Really need some help with this one... 1996 4x4 with a very obvious pulsating, rubbing, grinding sound/feel coming from the back end. I'm almost positive the rear axle-rod bearings are worn. But no fluid leaking on the inside of the wheel yet. Brakes are good, tires are w/in 7K miles of being new... so its gotta be in the axle area.

I already replaced the rear axle bearings about 90K miles ago, used keeper bearings (bearing with seal) since the axle-rod was a bit worn in the bearing spot. Now it appears that the axle rod might be worn again (in the new bearing spot).

I there another alternative for extending the life of the axle-rod again? Or do I need to pay $400 for a new set of axle-rods?

Any chance a worn drive shaft pinion bearing could be making this much noise in the differential?

I'm really stumped and need a good alternative and troubleshooting approach before tearing into the rear end...

thanks very much

 

I'm assuming you mean axle shaft. It could be either the shafts are worn, the bearings are bad, or the rear-end is completely toast. First things first, put the truck's rear up in the air on jackstands. Chalk the front wheels and very carefully have someone put the truck in gear running and watch the wheels. If they wobble, it's indicitive of bent axle shafts. R&R. On the other hand, service the rear-end by removing the cover and old fluid, use brake cleaner to clean the internals, and R&R with new fluid. If this doesn't help, it may be time for a rebuild.