replacing just 1 piston
 

Hey guys, I've got a 5.3 with low comp in one hole, hopefully just rings but likely a broken piston. Anyone ever replace just one piston and rings? Would a used piston work? Thanks.

Yes it has been done before. As long as the cylinder wall is ok and the piston to wall tolerance is within spec you should be ok.

A good used piston is ok as long as matches the rest in weight. I would how ever use new rings.

They wear specific to each cylinder so it may be good in one and when you switch it to another block it may have sealing issues...

I've done it once. As said, it mostly depends on the condition of the cylinder wall, the condition of the rest of the engine(and mileage), and what type of failure you had. You honestly won't be able to make that call until you open it up and start checking things.

When you get it apart, post up what you find. Then we can help you better.

A piston broke in my suburban earlier this year, it was smoking big time out the exhaust.

This past January I did change one piston in a 06 SS, its been bugging me since.

How has it been bugging you? Just compression/oil sealing issues?

if he's like me, it's just knowing that one is not like the others...

Growing up in backwoods Mississippi, I have seen some sketchy shit.
I helped my buddy pull apart his 'built' 5.0 after his cousin sprayed the hell out of it off the line and blew apart the intake.
That engine had 3 (three) different brands of pistons in it. Funny part is that it ran like a raped ape before they blew the top off of it.

It bugs me cause there is one new piston and 7 used.

Ahhh ok, that makes me feel better. So have you guys noticed much variation in the weight of factory pistons? I haven't got it torn down yet, but for whatever reason if I'm not able to weigh the burned piston, what's the chances a used (or new) piston is going to be close enough?

I didn't and haven't had any problems. Last time at the track, the truck ran consistent 11.6x's all day, broke out in the final & took home a runner-up trophy.

Bottom line is, until you tear it down & check everything, you'll never know if you can or can't get away with it. The block is more of a concern than the piston at this point.