I have an 06 Colorado Z71 4x4 with 32,000Km's (19,880mi.) on it. The front brake pads have virtually no wear on them, but the rear shoes are completely worn. This would be the first vehicle I own that A) wears brakes that fast; & B) wears out the back first. On any other vehicle I've previously owned, I usually do the front twice over before the rear needs doing. That can't be right? Anyone have any ideas on why this might be, or anyone with a Colorado noticing the same thing?