Help with diagnosing a strange sound

[Baffled Spoon]

Hi all,

I was hoping someone could help diagnose a strange noise coming from my parents car (a 2005 Mazda 6 1.8 with circa 63K miles). My dad described it as a “roar” coming from one of the wheels which is constant at speed and gets louder under braking. Is this likely to be a wheel bearing?

Also can anyone recommend a good garage to fix the problem around Canterbury?

Cheers, Spoon

[morgrp]

Wheel bearings tend to make more noise the faster you go or if you load them up in a bend - is it not just tyre noise?

[Tallbut Buxomly]

Nationwide autocentre broad oak road. I get them to do all the work on my cars.

[zelbo]

Wheel bareings i would say, is the noise louder tunring one way or the other ?

[Baffled Spoon]

morgrp said:

Wheel bearings tend to make more noise the faster you go or if you load them up in a bend - is it not just tyre noise?

It's not just tyre noise sadly, the noise is not loud at town speed but becomes aparent at motorwaty speeds. Also I was told that it gets louder when braking.

[Baffled Spoon]

Tallbut Buxomly said:

Nationwide autocentre broad oak road. I get them to do all the work on my cars.

Thanks, I will pass this on.

zelbo said:

Wheel bareings i would say, is the noise louder tunring one way or the other ?

I wasn't told, but will ask my parents to find out.

Is the fact that the noise gets worse under braking consistent with a bearing issue?

[Eggman]

Sounds like a brake pad might be worn down to the metal / damaged / got a stone caught in it etc. It might be down to a seized caliper, in which case the disk will be noticeably hot after normal driving. Someone needs to take the wheel off and have a look.

[Baffled Spoon]

Interesting suggestion about the seized caliper. I assume it would not affect braking too noticeably in most conditions and that it would still brake staight in normal use unlike it there was a problem with the pads, so maybe not noticeable staright away as a braking problem. Not sure whether a seized caliper would cause more noise the faster you went though?

Can a worn wheel bearing cause issues/ noise under braking?

[davepoth]

Baffled Spoon said:

Interesting suggestion about the seized caliper. I assume it would not affect braking too noticeably in most conditions and that it would still brake staight in normal use unlike it there was a problem with the pads, so maybe not noticeable staright away as a braking problem. Not sure whether a seized caliper would cause more noise the faster you went though?

Can a worn wheel bearing cause issues/ noise under braking?

Conceivably yes it could.

[Eggman]

Conceivably, but really only if there was sufficient play in the hub to cause the disc to move relative to the caliper (in which case I would expect the noise might shut up a bit under braking) or to misalign shoes and drums (in which case I would expect the noise from the bearing to be joined by an additional racket from inside the drum when the brakes are applied). In either case, if the bearing was sufficiently knackered to have that amount of play in it I would be looking replacing it very urgently and wouldn't be driving the car in the meantime.

However, in practice the roller bearings used in many modern cars can produce a lot of noise without showing much play - a front bearing in swmbo's Punto has recently started to rumble slightly but the noise only varies with speed, not with braking or cornering. If it was a taper bearing, I would expect it to make more of a humming noise and for the noise to change a bit in corners. I shall still be replacing it at my earliest convenience and the car won't be doing more than very local journeys until I have - you do NOT want a wheel bearing to seize whilst you are driving along, believe me.

Anyway, since your Mum and Dad's noise seems related to braking, my first suspicion would be that there is some kind of problem with the brakes. As soon as someone with half an idea what they're looking for jacks the car up and spins the wheel the nature of the problem should become fairly evident.