Rear End Whine

[Plainjane]

I am new to this forum and really new to Powerstroke's in general. Purchased a 96 4X4 (86,000 mile) last year to pull our 5th wheel. I have a whine in the rear end. Have had the ring and pinion looked at and all appears good. No evidence of problems when the lub was inspected and changed as well. Verified the noise is coming from the rear axle assy.

The whine comes in about 25 mph and fades away above 35 mph. There is no real change in the pitch of the whine when I let off the throttle. I have had two mechanics, (one at the Ryder Truck Shop, and the other is my mechanic) tell me that it could be nothing at all. I would like to believe that but hate biting my nails also.

I appreciate any feed back or ideas you can share.

[redcrow5]

my rear end recently started doing the same thing. The pinion could be riding differently on the ring gear cutting a new groove. Mine turned out to be a broken differential shim causing that scenario.

[late_99_PSD]

Maybe look at your universal joints.

[nitrogen]

could even be something as stupid as cupped tires. i had a bad front end howl/whine, tires looked decent everyone said, but after 5 months of hearing it, i rotated the tires and the noise definitely moved to the rear. today when i looked a little harder there was def cupping starting to show