# Low-Speed, Front End Squeal, 06 Z71 Silverado.....



## Bulldawg76 (Apr 5, 2007)

at low speeds (best situation being a bank drive through) there's a squealing sound coming from the front end. Brakes applied or not, turning or straight-away, while slowly rolling, it makes that (not very loud) noise. What is it?

All I can think of are brakes or cv's. I'd hoped after the first service that lubing the points in the front might get it. I mentioned it to the service writer but did not push it as a big concern. Even now it's not a big deal and it can't be heard with the windows up. But it's there. Anyone?


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## lake hartwell (Apr 5, 2007)

It sounds like brake rotors? How many miles? Under warranty?? It could possibly be a wheel bearing but if lower mileage it SHOULDN'T be but ???


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## MonroeTaco (Apr 5, 2007)

It's probably just brake dust on the rotors. Spray them off with a hose-make sure to get both sides of each rotor. All of my trucks have done that in the past, I don't think it's a big concern unless it starts getting worse-then you may want to have them checked for warped rotors or the pads being "glazed over".


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## Bulldawg76 (Apr 5, 2007)

yeah, that's what i was thinking.  certainly the main suspects are brakes, cv's and bearings.  

with the brakes, wouldn't the noise change while braking?  it doesn't seem to change.

also, this noise starts, so to speak, at 15mph and continues all the way down to stop.  alternatively, it goes away >15mph.  

it's not very loud so i guess i'm not too concerned and it is under warranty.  i know that hunting a noise can be time consuming and can result in just throwing parts at it, consuming more time.  it's a nuisance (right now) and if it was a bearing or a cv boot with a hole in it, it would only get worse, right?  

the truck has 5k miles, by the way, and it had been on the lot for about 10 months when i bought it.


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## W4DSB (Apr 5, 2007)

Cv joint would clunk or pop (Like this pop pop pop pop pop) not squeal or at least thats been my experience with them


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## MonroeTaco (Apr 5, 2007)

Yes, if it were a CV joint it would pop-especially while turning. But there should be NO way the CV is bad at only 5K. - bearings either. Are you sure its not a belt? If one's a little loose it will "squeel" at low RPM's.


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## chewie1014 (Apr 6, 2007)

It's not the CV joint...they don't squeel.  They click (or clunk or pop as others put it).

Don't rule out wheel bearings - regardless of how many miles the truck has.  A manufacturer defect or a bearing that wasn't greased properly during manufacturing could squeel early on.  Having said that, I doubt it's your wheel bearing.  A noisy bearing tends to go from bad to worse pretty quick.  A squeel in the bearing is an indicator that it's not greased properly - which leads to friction and heat (especially at high speeds) - which leads to more noise - ending in failure.  If it's not gotten any worse with regular driving, it's probably not a bearing (notice I said probably).

Sounds like brakes - more specifically sounds like you've got a loose brake pad that's leaning against the rotor when you drive.  The fact that you hear it more pronounced at slower speeds and driving through corners makes me think it's your brakes.  Brake dust can be a lubricant (think of it like graphite) and cause the pads to move around a bit in the caliber.  If it moves enough it can lean against the pad and cause a squeel even though the brakes aren't being pressed.  Usually the squeel would go away or change during braking, but not always.  Especially if the pad has been broken (thus making it easier to lean on the rotor) or become unevenly worn (as a result of leaning on the rotor).  If either is the case, it's entirely possible for the squeel to continue while braking.

Another thing to consider is the brake caliber.  I had a GMC Jimmy that developed a bad squeel on the front right after replacing the front calibers, especially during braking or taking corners.  I knew it was the brakes because I could see unusual and excessive wear on the pads and rotor, but did everything short of blowing the thing up and couldn't get the squeel to go away.  Since the squeel hadn't been there before replacing the calibers, I decided to replace the right side again and see what happened.  Instantly cured the squeel.  Being curious, I wanted to find out why that happened.  Ends up the slot where they pads sit in the caliber was slightly larger than spec.  It was so small that you couldn't visually spot any difference, but large enough that the pads were able to move more freely in the caliber allowing them to lean against the rotor and shimmy around during braking - both causing the squeel.  All that just to say that it's possible your calibers or pads could be slightly off spec resulting in some sort of friction or looseness that causes the squeel.

I'd start with the pads first.  That's the likely culprit.

HOWEVER, since it's under warranty, I'd take it to the dealership and make it their problem.


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## chewie1014 (Apr 6, 2007)

One other thing to consider - MonroeTaco's question about belts made me think of it.

The tensioner pulley on your belt system could possibly be the culprit.  Since the squeel is most noticeable at low speeds and doesn't change during braking - it's possible that the tensioner pulley is failing.  You said it sat for 10 months at the dealer before you bought it.  If water got up into the pulley bearings and then sat for a while, the bearings could rust and develop a nice little squeel.  I replaced the tensioner pulley in my wife's Tahoe some time back with a used one from a junk yard.  It had some rust and squeeled right away.  I squirted a bit of lube spray into the bearing and the squeel went away.  Sprayed a bit more for caution and it's never been a problem since.

If this be the case, the squeel should be noticeable even when the car is stopped with the engine running.  But it's possible that it may not squeel as loud at an idle RPM.  Lift the hood and have someone give it a bit of gas.  If it's the pulley, you should hear it.  If it's bad, get the dealer to replace it.

Also, I only mention the tensioner pulley.  Theoretically, it's possible it could be any of the other pulleys under the hood (alternator, water pump, etc.).  However, the other pulleys are part of larger components and tend to be better sealed and more resistant to water penetration than the tensioner pulley.  Not always, but generally speaking.


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## Bulldawg76 (Apr 8, 2007)

thanks everybody,

now i have a good feeling of the potential culprits and will have the ability to have more of a dialogue with the service writer (service writers generally love that) and will have to see what warranty service will bring.  Thanks again.


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