Chirping Obs 350...

silversport · September 17, 2008

Chirping OBS 5.7 350... I have an OBS 2000 Escalade (think '99 Tahoe/Yukon) that chirps...I had the fan belt replaced which seemed to stop the chirp...

...and after a few months it started again...took it back and my guys said "Your fan belt is bad."...I said, "You just changed it." and they showed it was and replaced it again...seemed to quiet again (except noticeable on wet days...parked outside) but now a couple more months...

I have several friends that have these OBS vehicles and I hear from them everything from "your water pump is goin'." and "your belt is bad." to it's normal...

Looking under th hood while it's running doesn't look like anything is out of whack or shaking any more than the engine normally does...

Your thoughts or experiences would be helpful...not a huge problem (yet) but irritating...

Thanks,

Bill

L29er · September 17, 2008

maybe your tensioner is weak and the belt is slipping, eventually getting bad enough to chirp after a while...

minibike132 · September 17, 2008

Isn't there two belts, one for A/C and another for the rest of the driven pulleys? If so I would go after the other belt and tensioner.

95Sierra2500 · September 17, 2008

Isn't there two belts, one for A/C and another for the rest of the driven pulleys? If so I would go after the other belt and tensioner.

They should all be one belt.

My guess is you've either got a pulley that isn't round/running true, or your tensioner is getting weak (it's just a spring, it happens over time). If you've got a dial indicator, take the belt off and set it up to check runout on each pulley. It should be within a few thousandths, I would think. If they all look good, I vote for replacing the tensioner.

One way or another, SOMETHING is causing abnormal wear on your belt.