[aulday]

Hi folks, in the past few weeks my beloved 120K mile Ampera has developed 2 noises.

First noise: Superficial sounding click that times with wheel rotation while braking around slow tight left hand turns. Sounds and feels brake related and not with any knocking force noticeable.

Second noise started today, this one I'm worried about: Only just started so it's very subtle, from 30Mph onwards it sounds like a distant motorbike in the front left footwell (it's not a distant motorbike btw 😂). It relates to vehicle speed, it is no where near as high pitched as the transmission bearing noise videos I've seen on youtube, but could it be the early onset of it?

At 40mph it sounds like a regular cruising motorbike rpm, increases with speed. No difference when in neutral, possibly slightly more noticeable under hard acceleration or regening in 'L' mode.

What are the possible causes? And what are the cheapest fixes for said causes. Do I pray it's a wheel bearing and change the fronts one by one, or go balls to the wall trans bearing?

Thank you!!

 

[h8ten]

I've read about upgraded axle nuts on the Chevy Volt forum, it may that your's is in need of replacement. I think that retightening it will only cure it for a short time.
The second noise could be a wheel bearing on the way out. This usually varies with the steering, louder or quieter as you steer the wheel. The 'big bearing' failure is more a sound like a circular saw that has just been powered off and slowing down and this is heard when the car is on over-run and slowing down.

 

[aulday]

Thanks mate, yeah I'm really hoping it isn't the trans bearing, it does sound different, more like humming / 2 stroke bike-esq. I have a rear bearing going to so think the ampy needs some deserved attention.

Just checked recent MOT, the clicking is prob related to these advisories (although CV boot looked fine when I checked briefly). But could be disc / pads:

Repair as soon as possible (minor defects):

• Offside Front Drive shaft joint constant velocity boot severely deteriorated (6.1.7 (g) (i))

Monitor and repair if necessary (advisories):

• Front Brake pad(s) wearing thin (1.1.13 (a) (ii))
• Front Brake disc worn, pitted or scored, but not seriously weakened x2 (1.1.14 (a) (ii))

 

[NathanP]

From your description of the second noise it sounds like wheel bearings and not the transaxle bearing...and at 120k wheel bearings would be a normal expected wear and tear item...they will probably just get worse gradually and slowly unlike the transaxle bearing which tends to get much worse very quickly...

If you search on here I think there was a thread about wheel bearings and the good news were they were fairly standard GM parts bin stuff so cheap and easily obtainable...

Hope you get it sorted ok - nothing to panic about at this stage though I think...

 

[aulday]

Thanks chaps, I will drive it some more and aim to change the wheel bearings as they're cheap and easy! Fingers crossed T

 

[donald]

Hi folks, in the past few weeks my beloved 120K mile Ampera has developed 2 noises.

First noise: Superficial sounding click that times with wheel rotation while braking around slow tight left hand turns. Sounds and feels brake related and not with any knocking force noticeable.

Second noise started today, this one I'm worried about: Only just started so it's very subtle, from 30Mph onwards it sounds like a distant motorbike in the front left footwell (it's not a distant motorbike btw 😂). It relates to vehicle speed, it is no where near as high pitched as the transmission bearing noise videos I've seen on youtube, but could it be the early onset of it?

At 40mph it sounds like a regular cruising motorbike rpm, increases with speed. No difference when in neutral, possibly slightly more noticeable under hard acceleration or regening in 'L' mode.

What are the possible causes? And what are the cheapest fixes for said causes. Do I pray it's a wheel bearing and change the fronts one by one, or go balls to the wall trans bearing?

Thank you!!

These are bog standard failure modes for the Ampera and you've clearly not been doing your forum homework properly, young lad. Detention for you!

Clicking is loose hub nut, rumble is wheel bearing.

Look 'em up. Easy fix.

 

[aulday]

Yeah I checked the lug nuts immediately anyway, all were super tight. I'm very familiar with bearing noise from prior vehicles, and I've never heard one sound like a motorbike before so I'm sceptical. Hence wanting to check whether early stage trans bearing noise could sound this way.

Also not wanting to assume from other forum posts when it could mean life or death of my motor.

That being said, lets hope it's simple and thank everyone for their input!

 

[Squasher]

Not the wheel nuts, the hub itself. Mine's just started making the clicking noise when pulling away and lifting off. Due my annual service & MOT in May.

 

[aulday]

Oh right! 😂 Got the wrong term in my head. Bearings and hub nuts coming up then 😎

 

[donald]

Technically the hub nut is use once and the threads stretch (and continue to stretch over time, hence the common 'fault').

So proper way is buy a new hub nut. Giving it a tweak will deliver the requirement for now, but don't go putting massive over-torque on it. Jut a sweet little 'nip up', should do it.

But TBH, might as well just ignore it and swap both bearings sometime soon, it is a hub assembly type, when one goes the other is not long behind.

Common issue on the GM Delta chassis. No big deal, it's routine maintenance.

 

[aulday]

Yeah I'll just change them, not a biggie, brilliant vehicles imo 👌

 

[Huw2997]

Have a slide hammer handy, the hub corrodes into the housing and can be a struggle to remove. The YouTube video from California does not apply after a few salty winters over here!

 

[aulday]

Thanks!

 

[Chris O’Neill]

Easy way to tell if it’s a wheel bearing, anything over 40 mph and you’ll hear it.
Also, if you turn left and it gets noisy, it’s the right side as the weight is shifted to the opposite side of the car, same for the other way.

 

[donald]

I've never been able to determine left or right accurately from cornering direction alone. I think it depends on the bearing design whether it is noisier on l or r bends.