'97 5.7 Piston Slap

[PharmZ71]

Question:

 

For the longest time I had a ticking lifter, turns out it was a worn rocker arm stud...mechanic pulled the head, replaced the stud. Got the truck back and it had a god-awful knock...LOUD when cold, but quiets as the engine warms...but is still there. Truck idles fine, oil pressure is fine, tows fine...

 

Mechanic told me (and I sort of trust this guy) that the knock was there before, but the computer was retarding the timing (or something like that) when the rocker arm was all messed up. The truck had a Hypertech (Now tuned to stock) and he claims the engine was overreved, which may have misshaped the piston, so now I have a slap. He claims that he's seen this engine go 200k with a piston slap.

 

Anybody heard of this or is he full of s**t?

 

Thanks for any advice!