2002 GMC Yukon AC Belt tesnioner makes noise at 2000 rpm

richardlogue · Posted at Sat Jul 26, 2008 12:56 pm

Noises problem
2002 GMC Yukon V8 Two Wheel Drive Automatic 105000 miles
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I have replaced my belt and tensioner and it still makes a squeeling noise at about 2000 rpm. The tensioner starts flapping when the belt starts to slip. I have also replaced the ac compressor and the pressures are 35 low and 225 high. The ac is on a separate belt with only a tensioner. This is the 5.3L engine. Any suggestions?

merlin2021 · Posted at Sat Jul 26, 2008 1:29 pm

Take the belt off, and try to spine the A/C puley and alternator, we are checking the pulley bearings for roughness or binding, if it has an idler check that one too.

richardlogue · Posted at Sat Jul 26, 2008 1:39 pm

I have replaced the compressor and the tensioner pulley. There is no idler pully. The pressure on the AC is 35 psi low side and 225 high side.

merlin2021 · Posted at Sat Jul 26, 2008 3:34 pm

Do you have a 5.7? If yes check the pulley on the crankshaft, some of them don't line up with the rest of the pullyes, and need a new harmonic balance. You will notice it by the belt hanging over the end of the pulley.