'11 Tahoe LT - New Rotors at 28,000!?

[Tahoe41]

So for about a week now I have been hearing a strange "whistling" or "whining" sound coming from what I believe to be either the engine compartment or wheel area. It seems to come on around 20-30 mph and goes away around 40-45 mph.

I took my LT to my nearest friendly neighborhood Chevrolet dealer and explained the odd (and new) sound. I purchased the truck used at 19,000 mi and never heard it before. An hour or so later I get a call from the dealer advising that they did in fact hear the sound I described during a road test. They put my truck on a lift and ran it, and didn't hear the sound anymore. Their diagnoses, tire noise.... I don't believe this is correct. I have heard tire noise before (not on this vehicle per se') and it sounds more like a rubber friction noise. Mine is definitely more or whine.

While at the dealer, he said they also found a "frozen" caliper pin. By frozen I took this to mean seized and not frozen frozen, as in Northeast Ohio winter frozen. It is 20 degrees out now btw.

Anyway, he said the truck needed new brake pads and rotors at the front end. I wish I would have asked if this premature replacement was caused by the seized caliper pin, but in my anger of hearing $290 plus tax for the job (at 28,000 mi) I just told him to fix it.

I picked the truck up a couple hours later and the noise is still there.

Any Tahoe experts out there please feel free to chime in. My unexplained (or misdiagnosed noise) rotor issue, etc. Thank you

 

[chevydipper1500]

If I understood you correctly this happens only upon braking. My bet is your are hearing the moisture evaporating very rapidly from your rotors. I always try to explain it to my customers as the "Tea kettle effect". If you park your vehicle in a garage that is warmer than the outside air condensation collects on the rotors and when you apply the brakes this creates friction and friction creates Heat and heat causes water to boil boiling water creates steam and steam makes your brakes whistle like a tea kettle. In my professional opinion you did not need brakes.

 

[Tahoe41]

Thanks for the reply. The noise comes on and makes almost a "hiss" sound is perhaps a better way to describe it. It's during acceleration, not braking. It seems to cut-off around 40mph and sooner if I let off the throttle. I'm at a loss for it's cause

As for the brakes, I'm wondering if the frozen caliper pin could have caused rotor damage (i.e., scored it) necessitating their replacement? Or at least one of them, but why replace only one.

 

[samotahoe]

caliper pin being fozen? possibly, if it prevents the pad from retracting after applying the brakes. as for your hissing noise sounds like it may be something with the exhaust or something in the engine bay that might be the culprit. really hard to tell a noise if I don't hear it.... but in any case it would be best if you drive around try with the window up or down. no other obstructing noises, ie. stereo or climate control off. and see if you can distinguish if its coming from front or rear of vehicle? maybe narrow it down to left or right side? and if it sounds like its coming from the cabin or an actual engine noise or suspension. maybe exhaust.... you might want to check the stereo out, a poorly wired speaker can make a whirring or hiss noise while under acceleration also. but if you turn it off it will go away. Same thing with climate control. Try with it on and with it off.

Basically try to narrow it down to where its coming from to help make your own diagnosis, that's what the techs are going to do anyway.

 

[retro_flyer808]

Sorry to bump this thread, but I recently has a very similar, if not the same problem with the front rotors on my 07 LT3. They would make a loud creaking and grinding sound when I breaked at lower speeds (35-). I took her in to the Chevy dealer and they could not find the problem. Unsatisfied and frustrated, I took it to a different Chevy dealer and after a very brief examination, I was told that my rotors were warped and corroded! The pads were worn down to almost nothing (far beyond redine), which shocked me because they were replaced less than a month ago. When they checked the calipers, they found multiple signs of fetigue and corrosion. I ended up having to spending 2000+ on a new rotors, calipers, and pads for my LT. Now she runs like a charm but it still bothers me that I had such a major problem with my front end braking system. I am always cleaning my car because of the slat air and unfortunately, that was not enough to prevent my entire front end braking system to fail! The good news it that my rear rotors/calipers are in near perfect condition!