Flametop

anyone know about a typical problem that causes a squeak in the belt/pulley system? I'm thinking I gotta get a stethoscope to track down the source of the noise. '06 convertible

Walt White Coupe

Here is what I experienced with my 05 when the main belt started chirping at 20,000 miles. Mine was still under the original warranty and the dealer replaced both belts. 100 miles later the chirping returned. Dealer ended up over the next three months keeping the car in the shop for a month. At different times they replaced the:

1. Tensioner Pulley
2. Idler Pulley
3. Power Steering Unit
4 Water Pump Pulley
5. Alternator

They finally determined that the flex coupling in the crank pulley (i.e. Harmonic Balancer) had failed causing the outer pulley to wobble enough to misalign the main belt and cause the chirping.

I'd recommend that you look at the crank pulley with the engine running on the passenger side with a strong flashlight and see if the pulley is wobbling. The pulley has grooves/ribs in it and the pulley, in the ideal case, should look stationary with the engine running.

Unfortunately, if it looks like it's wobbling, there is no out of limit GM specification for acceptable wobble. Basically, if the wobble causes the belts to chirp, then it's out of limit and the crank pulley has to be replaced.

Flametop

Thanks Walt! I think you're right on. I have already noticed that the H. Balancer looks to wobble too much. I was hoping it would be something with a simpler fix! The odd thing about my situation is that the noise goes away once the engine reaches normal temperature. Thanks, Rick

danzan

I had a similar issue with my C6 and it turned out to be the harmonic balancer.....say that 3 times fast

Walt White Coupe

If it goes away when the engine warms up then it's probably not the harmonic balancer. Get out the stethoscope.

Flametop

Thanks guys. Could be two separate problems maybe. I'm pretty sure the harmonic balancer wobbles more than it should, but the squeak could be a different problem. Too bad it's not as much fun to work on as it is to drive!!

gar4403

My slight chirp at 20k miles was a loose harmonic balancer bolt. Had the bolt & balancer replaced. Information found on this forum led me to remove both belts in order to isolate the problem. (note: only ran for short amount of time) My noise was still there, which indicated a balancer problem.

If the noise goes away, could be a bearing, idler, pump issue. Good luck.

american thunda

My car just started doing this a few weeks ago.... Im in the middle of a underdrive pulley install right now.... Its not fun at all

NYC6

Just noticed a chirp in mine this past week end. My car is S/C'd so it complicates it a little. I better have a look at it. These things dont get better on their own.

Flametop

Thanks guys! Great forum! Nice to have new friends!!

Vette5.5

While another vehicle entirely, Ford full sized pick ups and vans were famous for this on damp days. Changing to Goodyear Gatorback belts usually solved this. Not saying this will solve your particular problem, but if thinking of changing the belt anyway, what the heck.

danzan

My issue went away when the car warmed up and when the H balancer was replaced,so did the chirp.

amusquiz

I just bought a 2007 Coupe from a pretty reputable used car dealer here in San Antonio, TX. Everything was good for a few days until there was a significant amount of belt noise. I took it back to the dealer and they replaced the belts. The belt squealing went away, but now I hear the chirping and it's driving me crazy. I knew the used car dealer wasn't going to do anything about so I took it to the chevrolet dealer. The dealer isolated the chirps to two tensioners and their pulleys. After reading this thread I went to the dealer in person and insisted that the source of the problem was my wobbly harmonic balancer. The (larry the cable guy looking) tech said "they all wobble." I still insisted and my service advisor called the service manager Anthony over. Anthony was wearing a 50th anniversary vette shirt. He looked at the pulley for about a minute and said, "yeah it's wobbling and that's probably was causing the tensioners to make that noise." I was happy because the balancer is a warranty item and it isn't going to cost me anything. I'll post updates, but Anthony said they are going to start with the balancer and then "walk" and adjust the rest of the pulleys to try to get rid of the chirping.