First of all it is not the startup clatter/piston slap noise. I have had that since the truck was new and that is not it. Now...

For the past two week I have been hearing a stange noise comming from the pass side of the motor. It has a sound somewhere between a belt squeek and the sound of a bad bearing (metal on metal). It is very loud on startup then gets quieter and starts to sound like a tap on the inside of the engine. The tap sounds like taking a small hammer and tapping on a solid piece of Al. The tap also has two tones like tick(loud), tack(soft),tick, tack.... I only hear it at idle and goes away with rpm. It is the worst whenever the engine is cold and usually goes away once it reaches operating temp but not all the time. Please help me. I have already been to the dealer but it wasn't doing it while I was there. They said to bring it back later in the week so they could keep it over night and hear it on startup. Greg, is this what your bent pushrod sounded like?

 

It could be a pushrod, but none of mine were bent when I checked mine. It could be a lifter that is having a hard time pumping up. Your not spraying yet, are you? I wold leave it with the dealer overnight, that's what I did and how they found my problem. Sorry, I'm not much help here. Pushrods are easy to check, it oly takes about 1.5 hrs to check all of them. Just make sure you have at least 2 good quality 6 point 8mm sockets. I did mine one at a time. Just take off the rocker , pull the pushrod, roll it on a good peice of glass and look fo a gap. These ave a ball on the end and don't always roll smoothly, just look for a bow on the glass.

 

No, i am not spraying.. yet. I am probally just going to leave it with the dealer one night and see what they say. Another guy on LS1 gave me something to check that is real easy so i will try that first. I hope it is nothing major.