True, it could. I can't think of anything inside the diff that could cause this, except for bad bearings, which you would hear going down the road.

Another thought -- do the rear wheels hang roughly even with the car jacked up? If you have something going on with the suspension causing one side to extend more than the other, the drive axle on that side might bind more. They aren't made to work well at really extreme angles.

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1981 Mercedes 300TD, 1994 Honda Civic Del Sol
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Another thought:

The axle shafts suffer extreme angles when the back of the vehicle is lifted from the pavement with the wheels hanging. They were never designed to operate at these angles. One axle could definitely have quite a bit more friction than its twin.

If the brakes are not dragging, get the vehicle off the jacks and ignore the "problem" before you create a serious one.