Just rebuilt my 5.7 vortec. Replaced everything. Everything except the pistons and rods. I had two that were seized so I replaced #1 and #2. Put it in the truck and it had a rod knock. So pulled the pan and replaced every bearing in the truck. They had a few scared, but didn’t look bad enough to cause a knock. Cranked it and it still had the exact same rod knock. The knock is on the new #2 cylinder it sounds like. Am I actually hearing a rod knock or is it something else. Thought I would get some thoughts on it before I tore it back apart. Any info will help.

 

Did you check piston to cylinder tolerence?

 

No I didn’t. I put the exact same size rod and piston that came in the motor. So that was the last thing I was thinking about.