how do i remove the rear axle bearing and seal in the differential housing.

Sounds like you have a semi float axle, will need to remove the diff cover and drain, you will see a cross threaded pin that you unscrew, may have to spin gears to see it, when removed you will need to push the large pin that the cross pin held in place, after removing this try not to do any more gear spinning as this will allow spider gears to fall out of place, gently push the axles in and a "C" clip should drop off each end, may need to coax them off because of thick fluid, you can now remove axle shafts straight out, the seal and bearing will be at end of axle tube, pry out seal, use puller to remove bearings, even though only one may be making noise I always recommend replacing both when tore down this far, clean area and install new bearings and seals with correct drivers, reverse teardown procedure and refill with correct fluid.

There are two types of rear axle, the c-clip type and the non-c-clip type. C-clip type: remove wheel, brake drum, differential cover, differential gear shaft retainer and shaft, c-clip, axle shaft, seal, bearing. Reverse procedure to reassemble. Use Loctite on gearshaft retainer and tighten to 14 lb-ft. Tighten diff cover bolts to 30 ft-lbs. For non-c-clip type: Wheel, brake disc and caliper, or brake drum, axle retainer nuts,axle seal and bearing assembly. Split the bearing retainer with a chisel, press bearing off axle, remove axle seal and retaining plate. I'm pretty sure you have the c-clip type on a 2500, but I gave you both procedures anyway. Good advice from raierron also, but use the Loctite and torque wrench..

I HEARD THAT NOISE FOR OVER 10,000 MILES ON MY 199 DODGE RAM VAN 1500, AND CHECKED EVERYTHING INCLUDING DIFFERENTIAL GEARS. I FINALLY PULLED THE RIGHT AXLE SHAFT AND FOUND SEVERE WEAR SPOTS, ALMOST AS THOUGH ETCHED INTO THE AXLE AT THE BEARING AREA. I FINALLY LOCATED A USED AXLE IN EXCELLENT SHAPE. THE BIG PROBLEM IS TO REMOVE THE BEARING. I GOT THE OIL SEAL OUT IN PIECES WITH A SHARPENED SCREW DRIVER. I BUILT A PULLER, BUT IT WON'T BUDGE THE BEARING. SEVERAL MORE EXPERIENCED MECHANICS HAVE TOLD ME I WILL HAVE TO DESTROY THE BEARING TO GET IT OUT. ANY COMMENTS ON THAT?