Also look at the tunnel coolers to determine the year. '03 had the coolers on the outer corner of the tunnel, '03.5 and newer had them running more down the center. Problems I've noticed on mine: pull the front side panels if you ever get the chance and look overall for cracks in the welds. Had to replace an a-arm this year and found 4 small cracks in the bulkhead. Not too big a deal, just had them re-welded/re-inforced. Had the re-inforce the steering support (even had to fab an aluminum support for more strength)...of course I have risers. Check the can along the chaincase, i bought mine with aftermarket and whoever installed it didnt account for clearence. It was rubbing a hole in the case cover. Mine had SLP single on it, east to correct. I would check to see if it has outer running board coolers (edge of the boards). I disconnected the hoses on mine and plugged them. If you catch a rock hard enough and rupture that, could make it awful hard to get back to the truck!