I have a 5.3L with 240k on it that has a belt squeal problem so far i have replaced everything but crank pulley that the belt touches and it still squeal at idle, I have used gates brand belts and dayco brand belts when i replace the belt it will not squeal for about 3 weeks then start out of no were any ideas?

 

I've never had a belt squeak in 269K miles, but the tensioner does make some noise similar to that. Sounds like you have replaced that already, so I'm not sure. I do only use the Gatorback belts. though.

 

try a dab of dielectric grease. if it goes away its either a bad belt or one of the smooth surfaces. I had a tiny groove in the upper pully and it would only chirp at idle.

 

Check to make sure its the right size belt.
I've had a couple of stores sell me the wrong belts. It might fit snug at first but an inch longer belt will feel tight at first and then squeak after a short period of time.

 

Take all the belts off and spin all the acceroies by hand and see if you get any noise. Did you already replace the ac belt and tensioner?

 

Does anyone know who makes the oem gm belts I didn't have to replace my factory belt tell 230k

 

Best thing to do is e-mail gmpartsdirect with your vin# and they should be able to get you exactly what you need. There prices aren't too bad either and they respond pretty quick to.
Its good to use them if you're ever in doubt about certain parts. At least you can get part numbers from them and search for a better price elsewhere.

 

My truck always always always squeaks with anything but oem belts. I have tried them all gates, goodyears, cheapo off brands, etc. oem belts from the dealer never squeak at least for me. Apparently my truck is a snob.