My oo gmc bounces in the rear like crazy when hitting a bump. I noticed it sits about 1 inch lower on the driverside rear than the passenger side. My first guess is a bad shock but i dont know if a shock would affect ride hieght. It also has the same bounce at about 50mph untill you reach about 52mph. I have had tires & wheels balanced. The truck has 101000 on it and the shocks are original bilstins.