I just installed front and rear pads on my 2002 3500 c/c dually 4x4 at 50,000 + miles, these were the original brakes from day one. Lots of towing! The front did not even look like they had worn hardly at all, the rear were ready, they might have gone another 8,000 miles or so. But I didn't want to risk eating a rotor. The new pads I installed were the best "ceramic" pads that Nappa sells, same as OEM. There were different part #s for front and rear. The only difference was the price and the front set had the stainless steel clips that go back in with the calipers. The pads looked identical except that the rear were champfered out on the edge of the pad material, my guess is to make it easier to install on the rear. It is a little tighter back there because of the cage that holds the caliper and rear E-brake drum assembly. The factory pads that came off looked identical front or rear. The new rear pads don't come with the stainless clips. But the rear calipers are equipped with them. I asked the GM dealer and they said to use the old clips over. The brake instructions said it was critical to replace the old clips with the new ones.I asked the GM parts guy if he could get the clips, and he said yes. But just the clips cost $87.oo just for the rear. I used the old ones over . Any GM tech have any ideas? Is it possible that there is a difference in the compounds in the pads? They look exactly like the same material to me. Any idea's would be appreciated. Thanks