[carkrazy1987]

The low compression could be froma bad valve. I work for gm, on the heavyline side, and very rarely that stock engines loose pistons or block damage. I see more often on 4.8, 5.3, 6.0 is a valve seat burnt. I have 2 6.0 and a 5.3 with burnt valves on the floor nxt to my tool box. One actually has a burnt exh valve on cyl #7 lol. What I'm trying to get at, hopefully they did a leak down test also, and not just going on a compression, could save u money.