This is about my brothers 90 GMC Truck 350.
5.7 EFI with A/C The belt tensioner at low idle with e AC on is making a terrbile sound, all parts, tensioner, belt, and idle pully are new from GM, the parts guy at GM has no clue why it is still making noise, at first it just looks like its a cheap replacment when compared to the orginal, but they say thats the only one. Ive tryed after market tensioners, but there even worse.
The truck does have 180k on it but idles smooth. if any one has run into this kinda problem and has a solution, please me know.
My email is bowtientx@aol.com

 

You sure it's the tensioner? try oiling it... Maybe it's a bad alt. or something...

it seems kinda odd that new parts will still squeel, have you tried playing with the tension at all?

good luck

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1985 Camaro SC - 2.8L, auto.

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