BrandonAGr

I have determined that the idler pulley on the ac belt of my 98 is causing a squeak, after taking the belt off and spinning it by hand it will stop spinning very quickly, unlike the other one that just keeps spinning. With no AC belt there is no squeak at all. I have tried to get one locally but all of the parts store just have the larger idler pulley for the serpentine belt. Trying the look up the part on gmpartsdirect also seems to just pull up the idler for the main belt. I couldn't find any other threads where anyone said where they got the pulley from.

Does anyone know the part number for the ac idler pulley? Will I just need to get it at the dealership?

DeeGee

From the parts manual:

For a 98 with an LS1

"Pulley Belt Idler" 12564401

I'd try one of the Forum vendors for the best price; Fichtner Chevrolet, Fred Beans or Gene Culley.

Gene Culley

Hi there,

To take care of it properly you'll need the new tensioner and idler pulley. There was a bulletin to take care of both!

Thanks, Gene.

Nitro Junkie

There are two separate belt systems on the C5. That is the wrong part number for the A/C idler. The correct part numbers are listed below:

Pulley, Belt, Idler - 12564401
Tensioner, Drv Belt - 12559325
Pulley, A/C Cmpr Belt - 12557334
Tensioner, A/C Cmpr - 12560345

Mike94ZLT1

Hey Gene, would the same bulletin apply to a 99? I got a squeal too that's not the belts (just replaced them) and I'm hoping its these things. Thanks!