Warped disc could sound like wheel bearing failure?

[NervousEnergy]

Hi, hoping for some input. I've come by a 2013 Aygo with 76K - there are a few minor issues which I'm working through but no rust, so keeping it for my youngest daughter. But, it has what sounds like a failing wheel bearing - except that there's no play in the wheel (the sound is obviously from the driver's side) and no change in sound when turning (every other time I've had a failing wheel bearing it's been very obvious). On the other hand, spinning the wheel shows some obvious binding, and you can see this clearly between disc and pads when the caliber is off (haven't taken the whole caliber off yet though - started raining). There's nothing to feel through the pedal, but you can hear a periodic sound when braking (also obviously drivers side). The discs are new - there was a pre-sale MOT with a failure for discs, so don't imagine the ones they put on were anything special. I've never had this kind of symptom with worn or dodgy discs, but could the "bearing" noise actually be just that? Pads and discs are a me job, but a bearing is probably a garage job - so would be nice if possible to narrow it down.
Thanks in advance:-)

[LunarOne]

A failing bearing won't always exhibit play, expecially at the beginning. But if it's not the bearing, the noise could be coming from the brake pads rubbing on the discs, usually caused by stuck or seized slider pins. You'll be able to tell if that's the case if you check the pad thicknesses and one is significantly more worn than the other. If that's the problem, just pull out the pins, re-lubricate them with an appropriate brake lubricant, and then replace pads and discs as normal.

Edited by LunarOne on Monday 9th March 14:33

[ARH]

Could be a tyre. Swap them from front to back to see if the noise moves.

[E-bmw]

ARH said:

Could be a tyre. Swap them from front to back to see if the noise moves.

Better if you are certain it is coming from the driver's side to swap side to side, it will be MUCH easier to tell the difference.

[E-bmw]

NervousEnergy said:

it has what sounds like a failing wheel bearing - except that there's no play in the wheel (the sound is obviously from the driver's side) and no change in sound when turning (every other time I've had a failing wheel bearing it's been very obvious).

You say it sounds like a wheel bearing, but can you be more precise as to what it sounds like as other things you say don't sound like wheel bearing?

NervousEnergy said:

On the other hand, spinning the wheel shows some obvious binding, and you can see this clearly between disc and pads when the caliber is off (haven't taken the whole caliber off yet though - started raining).

What do you mean by "you can see this clearly between disc & pads"?

NervousEnergy said:

There's nothing to feel through the pedal, but you can hear a periodic sound when braking (also obviously drivers side). The discs are new - there was a pre-sale MOT with a failure for discs, so don't imagine the ones they put on were anything special. I've never had this kind of symptom with worn or dodgy discs, but could the "bearing" noise actually be just that?

Hopefully when you answer the above questions this will become clearer.

[NervousEnergy]

Dear All, thanks as always for the quick and helpful replies:-)

E-bmw said:

Better if you are certain it is coming from the driver's side to swap side to side, it will be MUCH easier to tell the difference.

Or just put the spare on I guess?

LunarOne said:

But if it's not the bearing, the noise could be coming from the breake pads rubbing on the discs, usually caused by stuck or seized slider pins. You'll be able to tell if that's the case if you check the pad thicknesses and one is significantly more worn than the other. If that's the problem, just pull out the pins, re-lubricate them with an appropriate brake lubricant, and then replace pads and discs as normal.

The caliper is moving properly, and it's all too new to see any differential wear (new pads and discs immediately before we got it) so hard to tell unfortunately.

E-bmw said:

You say it sounds like a wheel bearing, but can you be more precise as to what it sounds like as other things you say don't sound like wheel bearing?

Droning noise that starts at about 20mph and gets louder and higher in pitch as speed rises (and independent of whether you are turning or not). When braking, there's a periodic speed-related 'scraping' noise. I'm struggling to describe it exactly TBH but...

E-bmw said:

What do you mean by "you can see this clearly between disc & pads"?

Yeah, sorry that was very vague. When you remove the caliper (part holding the piston - leaving the pads and carrier) then there's a gap of about 1mm between one of the pads and the disc with a much smaller one between the disc and the other pad As you spin the wheel, the gap progressively moves from one side of the disc to the other, so something is clearly not aligned. But you can't feel anything through the pedal at all, and it drives (and brakes) perfectly straight.

It occurs to that this could be both things - there's clearly something up with the RHS front brake. If this was any other situation (not brakes) where there were two identical things, you could diagnose by just (temporarily) swapping. Could just do that and take it 1km up the road? Not safe even for a short test?

Thanks again

[E-bmw]

NervousEnergy said:

Dear All, thanks as always for the quick and helpful replies:-)

E-bmw said:

Better if you are certain it is coming from the driver's side to swap side to side, it will be MUCH easier to tell the difference.

Or just put the spare on I guess?

But what you want to do is firstly see if the noise moves from left to right all in one go for ease. Then try front/rear.

LunarOne said:

NervousEnergy said:

But if it's not the bearing, the noise could be coming from the breake pads rubbing on the discs, usually caused by stuck or seized slider pins. You'll be able to tell if that's the case if you check the pad thicknesses and one is significantly more worn than the other. If that's the problem, just pull out the pins, re-lubricate them with an appropriate brake lubricant, and then replace pads and discs as normal.

The caliper is moving properly, and it's all too new to see any differential wear (new pads and discs immediately before we got it) so hard to tell unfortunately.

E-bmw said:

You say it sounds like a wheel bearing, but can you be more precise as to what it sounds like as other things you say don't sound like wheel bearing?

Droning noise that starts at about 20mph and gets louder and higher in pitch as speed rises (and independent of whether you are turning or not). When braking, there's a periodic speed-related 'scraping' noise. I'm struggling to describe it exactly TBH but...

Speed related scraping noise when braking sounds like something stuck in a pad, or a rusty lip on a disc, or a pad fitted incorrectly.

E-bmw said:

What do you mean by "you can see this clearly between disc & pads"?

NervousEnergy said:

Yeah, sorry that was very vague. When you remove the caliper (part holding the piston - leaving the pads and carrier) then there's a gap of about 1mm between one of the pads and the disc with a much smaller one between the disc and the other pad As you spin the wheel, the gap progressively moves from one side of the disc to the other, so something is clearly not aligned. But you can't feel anything through the pedal at all, and it drives (and brakes) perfectly straight.

Pad gap being larger/smaller is quite normal but not necessarily obvious.

The pad behind the calliper piston normally retracts when the brakes come off but the other one only when/if the slider moves back, so this one quite frequently is right against the disc.

First port of call for me would be remove calliper & then disc, clean the face of the hub to ensure no rust/debris behind the disc. Clean both disc faces also, clean/grease ensure the sliders are free to move, then refit all & see if there is still "run-out" on the disc when rotating it in the calliper.

[Metric Max]

As E- bmw said
"First port of call for me would be remove calliper & then disc, clean the face of the hub to ensure no rust/debris behind the disc"
.
Some years ago Mrs MM had a 406 company car which had a recurring brake vibration, and every 10K miles the main dealer fitted new discs but they obviously didn't clean the hubs of rust. As the rust expanded it pushed the disc away from the hub unevenly.
After it went to a different Peugeot dealer for a service and disc replacement the problem was resolved. They obviously did the job correctly
After that whenever I fitted new discs a very slight smear of copper grease was applied to the mating surfaces

[NervousEnergy]

Metric Max said:

As E- bmw said
"First port of call for me would be remove calliper & then disc, clean the face of the hub to ensure no rust/debris behind the disc"
.
Some years ago Mrs MM had a 406 company car which had a recurring brake vibration, and every 10K miles the main dealer fitted new discs but they obviously didn't clean the hubs of rust. As the rust expanded it pushed the disc away from the hub unevenly.
After it went to a different Peugeot dealer for a service and disc replacement the problem was resolved. They obviously did the job correctly
After that whenever I fitted new discs a very slight smear of copper grease was applied to the mating surfaces

Yes - definitely possible as it was done for sale. I'll try swapping tyres first then do this.


Thanks all