Looks like its a large scale problem after all... I have not seen a truck realted forum where its members have not mentioned this issue. I feel for you all with loud knocking engine owners.

 

Hey, sounds like the two of you have the same thing my truck has. It's a slight, yet noticeable ticking while the truck is warmed up. Mine is quiet at startup and then this ticking begins after I've driven it for a while and the engine gets fully warmed up. I can live with it as it is NOT the notorious GM Piston Slap. I've taken my truck to several places (including the dealership) to have them check out the noise. It sounds like lifter noise or what the other guys said it might be. Trust me, I've heard a 6.0L with the piston slap/knock people worry about and it is a hideous noise and it's noticeable all the time (at least on the one I heard). I can live with the slight ticking my truck has.

Plus, you gotta remember guys these are engines after all and they make noise. From my uncles new Vette with a 5.7L V8 to my girlfriend's Nissan Sentra they all make some sort of engine noise. Hell, even my work car ('02 Nissan Maxima) makes some engine noises that are what I consider more annoying than my truck's engine.

 

My '00 5.3 is starting to knock pretty bad on startup. Time for a new motor.

 

short skirts on the pistons in the 6.0 is what causes the piston slap and i can hear it when i first start it up and it only has 15 miles on the too.

 

So has anyone come up with proof that the "slapping/knocking causes any long term durability issues? GM says it will not cause the enignes to fail early and have been tested to 300,000-400,000 miles in durability tests.