2003 Pontiac Aztek

Brakes problem
2003 Pontiac Aztek 6 cyl Front Wheel Drive Automatic 67k miles

Rear brakes were changed and therewas a clunking noise comming from the rear brake system upon completion. So changed all parts thinking they were wrong parts, twice. There is still a clunking noise in the rear when brakes are applied and is 10 times worse when wet. Only when slowing down, letoff peddle clunking stops. Clunking occures only when peddly is applied.
What do you think my problem is?
August 10, 2009.

Do you have rear drum or disc brakes?