1997 GMC Suburban 4 x 4 Whining Noise from..

The rear differential ( i think) makes a high pitched whining noise when under acceleration.It sems to be tied to putting the drive train under torque.When I let off the accelerator and coast the whining stops and resumes when I accelerate again.
Help please?
What is causing this?
Thanks

Welcome to AF, tough to diagnose noises from this desk, your description sounds like a possible pinion bearing. Find someone familiar with this type of problem to road test the truck for a more definitive diagnosis. The diff. is full I assume.

Welcome to AF, tough to diagnose noises from this desk, your description sounds like a possible pinion bearing. Find someone familiar with this type of problem to road test the truck for a more definitive diagnosis. The diff. is full I assume.


Thanks and yes. Actually I had the diff. cover taken off today and re lubed to
check for damage. My repair shop says "replace the whole rear end"
At $2000-$2200
He says the cost to replace the gears and bearings is close to the whole replacement.
I am getting a second opp on it for sure.
Thanks for your help