Rear shocks stuck in high position on 2001 Buick Park Avenue

Installed new tires, fine after this. Short trip involving country roads, on trip home noticed car high in rear, looked at shocks, obviously in higher position. How to correct?

This type of problem on your 2001 Buick Park Avenue could be cause by a failed or disconnected ride height sensor of a failed air exhaust valve on the compressor. The first thing to check would be to see if the link that goes from the rear suspension lower control arm to the height sensor has become disconnected.
Thank you for your reply. I ended up taking it to the Buick garage and they fixed it. It was just what you described, the sensor was damaged and also the control arm connection.. Thanks again for your reply.