possible bearing prob
 

has any one had the bearing on the adjuster pully go bad. i have a tapping noise, really bad when cold on startup, but quiets down after warmup. everyone tells me its not internal. any suggestions????:?:

Yes it's very possible. I think GM only sells it as a complete unit, not just the bears? But you can repack them. Most of them now have a cheap plastic type seal, they aren't like the older style steel bearings.

Remove the pulley, then the metal cups, under that is the plastic seal. You can remove the plastic cover using s small screwdriver, like one you would use to repair eyeglasses. Then clean out all the old grease and repack it. On my 99 and 05 trucks I had to do this every 70K miles.

get a long screwdriver and place it on a non moving portion of the mount, you should be able to identify if that is where the tapping is coming from. i usually probe around in a bunch of spots to be absolutely sure. also, bearings tend to have play when they go bad, see if you can wiggle it any.

Maybe an exhaust leak from the manifold or EGR ??

loud tapping when cold
 

i dont know but when the engine is cold in the winter you can really hear it, sounds like a blown main bearing, only not. quiets down to a low noise when warmed up but still there. people tell me need new 5000 engine when the engine burns no oil or smokes. a main bearing bangs loudly ALL the time, not just when cold. how do you check EGR ????? i have no engine code.