GM Repair Questions? Ask a Mechanic for Answers ASAP
The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.
During mid production of the 2008 model year a design change was made to the front brake pads, pad spring clips, and caliper brackets. This new spring clip is designed to pull the pad off the rotor slightly more than the original design. This helps to reduce front brake noise, rotor pulsation, and helps to prevent metal transfer between the pad and rotor (scoring). The pictures below show the differences between the 2nd and 1st designs. When servicing a 2008 model, ensure the correct parts are used. It is not recommended to install the new/updated parts on a vehicle built with the original design parts due to future servicability concerns.
You may want to take the bulletin number which is pit4611 and have them inspect the brakes for this issue. The only way to get rid of the pulstaion is to machine the rotors.