Cupping on interior shoulders of rear tires

[CoryM]

If it is just the inside edges that are wearing, it's probably toe wear. Blown rear shocks will make for cupping across the entire tread, worse in the middle.
What tire are they? Some tires are very prone to cupping/noise just by design.

[ochy38]

Originally Posted by CoryM

If it is just the inside edges that are wearing, it's probably toe wear. Blown rear shocks will make for cupping across the entire tread, worse in the middle.
What tire are they? Some tires are very prone to cupping/noise just by design.

The tires are plane jane Bridgestone Insignias. I didn't think there was a rear toe adjustment on this car.. is there a bushing or something that could cause the toe to go out of spec? Seems to be happening pretty evenly on both tires. I'll take a closer look after work today but memory tells me that the wear starts at about center of the tire and gets worse the closer you get to the inside shoulder

Originally Posted by TOUGEghost

Lack of tire rotation.

What would cause this? Wheel bearing? something else?