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Discussion Starter #1
After 9K miles and 9 months, my 2012 Volt developed the bad motor bearing cage issue, resulting in a VERY pronounced and distinctive noise during low/medium speed strong regen ("L" mode).

After 15 days in the shop (bummer), I picked up yesterday. I didn't notice anything yesterday, but was on phone or listening to radio. Tonight, I thought I heard that distinctive "circular saw spinning down" noise. Turned off radio and rolled down window. It is for sure there, but much much quieter than before (for reference, still much louder than acceleration whine).

My question is (particularly for those who had he same problem/repair): is that noise (in quiter form) normal. I don't recall hearing it at all before my bearing problem-- but I am questioning my recollection/sanity.

I don't want to schlep it to dealer again if it it normal.
Thanks!
 

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When you get roller bearing wear the shaft(s) are pitted as well as the bearings.
 

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The thing with bearings is; they get worse or they don't. Give it a few thousand miles and if it gets noisier then take it back and get it fixed. If it doesn't, it is probably just fine.
 

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You could always go drive a dealer demo for comparison?
 

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Is it the same kind of noise or is it more of an electrical whine? I notice it as well, but only at the tail end (last 3-5MPH) and I hear it more as interference in the radio (making me think it's electrical and not mechanical).
 

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Discussion Starter #9
Is it the same kind of noise or is it more of an electrical whine? I notice it as well, but only at the tail end (last 3-5MPH) and I hear it more as interference in the radio (making me think it's electrical and not mechanical).
Same exact noise, just quieter. Different than the AM radio interference noise.

I will take above advice and just see if it gets worse.
 
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Same exact noise, just quieter. Different than the AM radio interference noise.

I will take above advice and just see if it gets worse.
Cnicholson,

have you informed your Volt Advisor so they can document it for you in case you have to take it back?

-Ian Chevrolet Volt Customer Service
 

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After 9K miles and 9 months, my 2012 Volt developed the bad motor bearing cage issue, resulting in a VERY pronounced and distinctive noise during low/medium speed strong regen ("L" mode).

After 15 days in the shop (bummer), I picked up yesterday. I didn't notice anything yesterday, but was on phone or listening to radio. Tonight, I thought I heard that distinctive "circular saw spinning down" noise. Turned off radio and rolled down window. It is for sure there, but much much quieter than before (for reference, still much louder than acceleration whine).

My question is (particularly for those who had he same problem/repair): is that noise (in quiter form) normal. I don't recall hearing it at all before my bearing problem-- but I am questioning my recollection/sanity.

I don't want to schlep it to dealer again if it it normal.
Thanks!
I think folks needs to understand why the sound occurs and what is replaced. Basically the bearings have an inner and outer race made of hardened steel that the balls ride in. They are spaced apart at regular intervals by a spacer, this unfortunately was made of plastic in at least some of the volt's (chevy hasn't really communicated if this was a bad batch, a part number error or a bad design) either way they are changing them out for metal spacer bearings now.

The noise you are hearing is when the plastic spacers break apart, this allows the bearings to move around in between the two race's and so the motor shaft is not properly held central anymore.

When you are engaging regen the motor is forced to one side axially, the rotor/stator distance is very tight, probably 0.020" (0.5mm) so it takes very little slop to allow them to touch. When they touch they make the sound of the saw spinning down, this is literally the sound of the rotor grinding itself again the stator, in the process they are both damaged and metal particles are shed inside the lubrication oil which could cause damage elsewhere.

When the bearing is replaced there are no parts of the old bearing left, it is entirely removed. So any residual sound is simply the electronic 'signature' of the PWM and stator poles sucking mechanical energy back into electrical energy.

If my car suffers from this bearing problem I'm going to insist chevy replaces the motor, its criminal that they put a plastic spacer bearing in a motor that is supposed to last 600k miles, there are countless examples of these types of bearings failing in vehicles so I have to assume they screwed up badly somewhere.
If the motor isn't replaced but just the bearing then the car could suffer failure in the future after the warranty has expired.

Remember the saw sound is not the sound of the bearing failing it is the sound of your motor grinding itself to pieces!!
 

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My Volt has the same issue

I was just told by my Chevy Dealer that my Volt has a bad bearing and the part is on backorder! No ETA! I am amazed by the engineering on the Volt, but with all GM products quality is not on the top of the list.
 

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I was just told by my Chevy Dealer that my Volt has a bad bearing and the part is on backorder! No ETA! I am amazed by the engineering on the Volt, but with all GM products quality is not on the top of the list.
I'm sorry for your trouble (had the same thing last year). What model year is your vehicle and what are the last 5 of your VIN. My suspicion is that there is a bunch of Volts made around the same time that have this failure-prone part in it. If you're someone with this part, it's not a matter of if as much as when.

Further, while I'm sure someone at GM has already had this thought, it seems like they don't want to actively solve it. Old school car company - if it's not broke, why fix it. Here's why you should actively replace the parts in the cars where it hasn't failed yet: your product is getting a reputation of being a great car to drive when it works.

My car has been in the shop maybe 8 times in the 15 months I've owned it. That's not a great record. More than once it was for more than 1 day. I've had significant parts fail on this car: I had a charger (not the thing on the wall, the thing inside the vehicle) fail because of a "voltage spike," I've had an air conditioning hose/coupler fail, and I've had this bearing fail. I'm pretty forgiving for the people doing the work when they have to wait for stuff (except the time where I was put in a smoker's rental car - that had to go) but I'm less forgiving of GM for not having parts available.

Failures happen. What's special about these failures is that they're hitting significant systems in this EV nature of the vehicle. Other people are having the same problems. Enough other people are having the bearing problem that it seems like there is enough data for GM to predict which vehicles will have this problem, and if they used this data to model which vehicles are likely to fail they can fix it. Is that what happened with the NTSC battery failure test? Did they offer to do all of them because it looked like good PR after being embarrassed by the explosion? I don't know, but they actively took care of it. The least they can do (well, it's not the absolute least they can do - they seem to be doing that right now by limiting parts availability) is prepare replacement kits and get these out to dealers who have sold or serviced Volts so that their customers don't have to wait an indeterminate amount of time for a repair.

Maybe we should just start a campaign of embarrassing GM by putting up on YouTube videos of how "quiet" our cars are...

Sign me frustrated
 

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Discussion Starter #14
As noted above, mine was down for 15 days--- and perhaps is not 100% fixed. I need to take it back to dealer so they can listen to current noise (I will also test drive a new Volt from there lot to compare sounds for normalcy).

This is a known issue. No reason why they can't have parts lined up to address this failure-- unless maybe scope is broadening faster than they expected.

Out of curiosity, do you drive in "L" mode normally (I do)? Wondering if this accelerates timing of the failure somehow.
 

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We are hearing about a lot of these bearing failures. We are also hearing that people are having to wait for weeks on end to get the replacement part. And during that extended wait for the part... Chevrolet is getting stuck with a big fat rental car bill.

Seems like Chevrolet could save a lot of rental car cash by keeping that part IN stock. Seems very wasteful. Furthermore it seems like they could save even more cash by designing the part NOT to fail in the first place.

This type of poor management is how car companies go bankrupt.
 

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Sky. Is. Falling. Being a little dramatic arentchya?
Just pointing out a reality. And lets not forget...

2013 owners are reporting heaters that fail to operate in cold weather.
2013 owners are reporting sticky steering racks.
2013 owners are reporting hands free operation with iPhone 5 and various Android phones.
2013 owners are very annoyed with the fact they cannot set the default charge to 12 amps.
ALL owners are complaining about chronic issues with RemoteLink and MyVolt features.

And perhaps several more chronic complaints that don't come to mind at the moment.

Makes me glad I leased a 2012 instead of a 2013 model.

At least we are not hearing about front strut failures as often now.
 

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Yeah, it would be interesting to have a table with issues vs. model year, to see if there is some kind of concentration of problems with certain model years.
 

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Discussion Starter #19 (Edited)
You don't have the right for your Volt to remain silent. (Noise post bearing fix)

My original test drive of the Volt had virtually no motor noise on acceleration or deceleration (other than a pleasing high-tech whine on hard acceleration).

I enjoyed this quiet EV performance for about 9000 miles in my 2012.

Then, the plastic bearing parts failed and car was down for 15 days.

Post-fix, the car makes a very annoying "saw spin down" noise on deceleration (especially in "L" from 40mph to 10 mph with light braking on top of "L" regen).

Shop says this is "expected" with the brass replacement parts. They said the last guy with the bearing fix also complained and GM said the new part is noisy. Live with it.

I called my advisor to lodge a complaint.

As an aside, the 2013 cars sitting on lots do not make this noise (per the service advisor that tested my car).

Speculation: They went with a plastic component because the brass one is too noisy But the plastic one (or a subset of them) fail quickly, so they replace with a part known to be durable but also known to be noisy.

The noise is not terrible, but I am NOT a happy camper. It's in the category of badly squeaking brakes on a new car: perhaps not a safety issue, but annoying.

My position: make my car sound like it did when it was new. Period.
 

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My position: make my car sound like it did when it was new. Period.
Agreed. It's one thing if the change was inconsequential, but the Volt's quiet ride is (or should be) a big selling feature. It might also be that other parts were damaged ...
 
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