2005 Silverado Belt Squeaking!

Hello,

Ok, here are a couple other possibilities and a simple test.

Since you replaced the Pulleys you can somewhat rule out the bearings on the Tensioner and Idler Pulleys. When you replaced the pulleys did you check to make sure they spun freely before replacing the belt? In some cases the after market pulleys will need a spacer behind it otherwise it will be metal on metal till wears groove in the mount.

Next is the Tensioner Assembly itself - While engine is running watch the tensioner does it appear to bounce around a lot? If so then you most likely have a bad tensioner. Which will cause a loose belt and the squeal.

A/C Pulley Bearing going - With engine off and using a spray lube, spray around the inner part by bolt and also behine as best you can. Then start the vehicle if squeal is gone for period of time then will need to either the A/C Clutch and Pulley Replaced or possibly the A/C Compressor.

Could also be either the Alternator Bearings or the Fan Clutch

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Ok, you may have a defective belt. I would take the belt back and ask them to defect it. Explain what you have done and all seems to lead to the belt. Make sure also that you give them all the details on the Make, model engine etc. Some belt have different pitches on the ribs which can cause squealing do to not seating properly in the grooves.

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