pinion shaft bearing. My gf 99 amigo had a whine under load in the rear, so i changed the fluid, milky coffee looking fluid. Changed it, whine still there and got worse. Pinion seal then broke, changed that and noticed the bearings were really loose. So, loose bad bearsing could be the noise itself or now that the bearsing are loose, the gears arent meshing like they should.

check the fluid

kevan

93 rodeo,3.2 manual, limo tint, nice sound system,keyless entry and a killer alarm, drop in K&N, 3 inch DOR lift, 32-11.50 BFG MT's, warn hubs zutah.com wheeler
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