I had rear brakes installed and rotors grinded. Now the car is severally bounding down the road and there is a smell of burn tire/oil. I took it back and they said the smell is typical of new brakes and they re-greased the rear, they also said I may need new caliper, but it was not bouncing before I took it in for new brakes... but it is still bouncing. have not driven it long enough for smell, wanted to get this message out for advise quickly.
What could cause the bouncing.