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Discussion Starter #1
For the last week i've been getting a humming noise when after letting off the gas as she slows down. From what I've read it's mostly the wheel bearings though unsure of which side or both. One member said he got his replaced under warranty around 50k. Is That true?

I'm at 32k but My 3/36 has expired 2 months ago (underdriven) and the powertrain doesn't cover shit lol.
 

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Levee
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I honestly don't think it's still covered under warranty. As far as the sound goes, you can tell if it's a wheel bearing as the sound would be there all the time, and gets louder or quieter depending on the direction your turning. If you only hear the humming while slowing down, that either has to do with the transmission, or mounts. So are you getting the noise constantly or just when you slow down?
 

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Discussion Starter #3
Just when I slow down and it doesn't make the noise when turning. I'll have to drive again to double check.
 

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Levee
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Then the humming is definitely not a wheel bearing. Hate to be the one to tell you that.
 

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Chevy Customer Service
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I checked the 2010 Chevrolet Warranty manual, Cliff, and see that wheel bearings are excluded from coverage. If you have further questions about what is covered by the powertrain warranty I'm happy to help! Please include your name and contact information as well as the last 8 digits of your VIN if you should contact me via private message.
Sarah, GM Customer Service
 

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Discussion Starter #6
Just came back from the dealership it was a worn left front hub bearing. Replaced and noise is gone. Yes to my surprise it was replaced under Powertrain warranty. :)
 

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Levee
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Just came back from the dealership it was a worn left front hub bearing. Replaced and noise is gone. Yes to my surprise it was replaced under Powertrain warranty. :)
Glad to hear that you got it fixed, it's just really odd that you only heard it when stopping. 99.9999% of the time, you will hear the bearing humming all the time and it will get louder or quieter while you are turning in different directions. I guess yours is the .00001% that defies that! Don't you just love cars!:laugh:
 

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Discussion Starter #8
It wasn't til the last few days I've started hearing the noise when turning right and thought it had to be the hub. Better safe then sorry :)
 

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Levee
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It wasn't til the last few days I've started hearing the noise when turning right and thought it had to be the hub. Better safe then sorry :)
Agreed! It's always better safe than sorry. Glad you now know what that sound is for future reference. And now you can understand what I mean by the sound getting louder when turning :). See some good learning experiences! Again, glad you got it fixed though.:smile1:
 

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These cars seem to have front wheel bearing issues, I have replaced two front one's on a low mileage 2009. Over 50 under 60K.
 

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According to GM engineers the problem isn't the bearing per say. Of course it is the bearing that ends up being the scape goat. They say the real problem is the front disc brake rotors being too small or not enough mass I guess(Saves weight). What??? Yep, apparently what happens is the rotors get really hot under hard braking. "So what!!!", you may think. Well turns out the Knuckle is also undersized to save weight, and that is where the bearing is housed. What happens when the rotors get red hot the heat get's dissipated to the knuckle which in turn dissipates to the bearing. Bearing gets excessively hot and melts the grease which leaks out. Eventually the bearing rids itself of all it's grease and "voilà", like driving an engine with no oil, we all know the end results. Cobalts with the bigger brakes have barely any bearing issues.
 

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I have this humming noise.
From both sides no warranty here but I gotta replace them it's getting louder and louder lol.

The guy below me sucks

---------- Post added at 03:42 PM ---------- Previous post was at 03:41 PM ----------

Could the messed up bearings cause my rotors to warp?

The guy below me sucks
 

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Nope, rotor warpage is caused by other than the bearing.
 

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I have '07 LS coupe 5 spd. Changed left front wheel hub at 140,000. Only indication was sounded like bad tire noise. Changed myself in about 45 min. Might be quite a bit to the theory on the heat transfer to the bearings. Got quite a few miles out of mine, but I'm pretty easy on brakes. Still original pads and rotors on front, but changed rear shoes at 148,000. They were only about 2/3 worn.
 
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