2012 Verano with 44,000 miles … My brakes seem to work ok except that after I press down on them I feel a thunk a second or two later . any suggestions ?
It is possible that this is not a brake issue, and instead has something to do with the shifting of an object that is loose in the trunk. Check the attachment for your spare tire, and also see if there is any “cargo” in the trunk that shifts its position when you brake.
Your motor mounts could be failing. Do you also hear this clunk if you accelerate hard from a stop?
Though 44K is early it could be, as lion9car said, motor/transmission mounts or could be a suspension part failed.
Could be the calipers aren’t sliding freely but on a 44K vehicle my guess is a suspension component is worn out. When you step on the brakes physics dictates the front of the car moves downward and the rear moves upward, and those movements are accommodated by the suspension system. By the posts here there’s a suspension component called a ‘link’ that tends to be a common cause for this.