[E92westy]

This started a couple of weeks ago and seems to be getting worse.
First thing in morning, drive off with no issues at all.
After about 15 minutes driving I’m into stop start traffic and when pulling gently away I hear a metallic grinding noise from the rear which is also rotational (ie varies with speed).
This gets worse as the journey gets longer and if I coast in neutral at say 15mph in the traffic it’s really quite loud…
Thought it might be brake related, pads dragging or handbrake shoes, so jacked the rear up last night when I got home and spun the rear wheels by hand – no unusual noises….
So it’s something that warms up and then makes a metallic grinding noise relative to vehicle speed. It’s also much worse when coasting rather than with even a tiny bit of throttle applied.
I’m thinking wheel bearing perhaps? Or any suggestions.

I suppose I’ll send it into the dealer for diagnosis, but I’m not sure the AUC would cover a wheel bearing as it would be “wear and tear” I assume?

[xenon]

Given the symptoms I'd have put my mortgage on a stone trapped between the disc and the tinny splash guard but you seem to have eliminated that. Wheel bearings usually rumble and don't come on suddenly. Any lateral play when jacked up?

[E92westy]

Originally Posted by xenon

Given the symptoms I'd have put my mortgage on a stone trapped between the disc and the tinny splash guard but you seem to have eliminated that. Wheel bearings usually rumble and don't come on suddenly. Any lateral play when jacked up?

I gave them a good tug (the wheels that is, before Will chimes in ) and didn't feel anyything untoward....

[M3-FAST]

+1 with the stone issue - I was about to post exactly the same as Xenon. I had the same noise on the M3 when I did the drifting day at North Wealds and a stone was trapped behind the disc backplate.

Wheel bearings tend to rumble or drone at higher speeds and when loaded up in corners, rather than grind at low speeds in my experience.

The only other rotational noise could be diff related, but given the symptoms, highly unlikely.

Sorry Westy, no idea pal! Have you tried driving round on a car park past someone, see if they can establish what side of the car it's coming from?

[Dr Dave]

Brake pad stuck in it's carrier; a simple strip out clean up lubricate and reassemble and all should be well. Any trapped small stones would also become evident.

[jonl1983]

mine does the same, was told it was the handbrake shoes

[E92westy]

Originally Posted by M3-FAST

+1 with the stone issue - I was about to post exactly the same as Xenon. I had the same noise on the M3 when I did the drifting day at North Wealds and a stone was trapped behind the disc backplate.

Wheel bearings tend to rumble or drone at higher speeds and when loaded up in corners, rather than grind at low speeds in my experience.

The only other rotational noise could be diff related, but given the symptoms, highly unlikely.

Sorry Westy, no idea pal! Have you tried driving round on a car park past someone, see if they can establish what side of the car it's coming from?

Deffo not a stone Paul. I only ever drive around car parks now as I'm too scared to park in tight spaces incase someone's watching..

Originally Posted by Dr Dave

Brake pad stuck in it's carrier; a simple strip out clean up lubricate and reassemble and all should be well. Any trapped small stones would also become evident.

Removed and cleaned calipers / pads etc tonight. Guess I'll find out if this worked in the morning....

Originally Posted by jonl1983

mine does the same, was told it was the handbrake shoes

Hmmm, when doing the NSR, I spun the hub without the caliper attached and there did seem to be a bit of drag on the handbrake, so slackened it off with the in hub adjuster. Again, guess I'll find out if this works in the morning.


I reckon after spending two hours removing and cleaning up the calipers etc, if it does it tomorrow it's got to be handbrake related or 'something else', in which case it's back off to the dealer....
Will update in the morning and thanks for the ideas!

[doubled87]

im hoping mine is a wheel bearing. Right rear i think. doesnt have to warm up but i thought it was the diff but doesnt really change when accelerating and decelerating.just gets louder the faster i go.
It really changes when cornering to the left at speed and it loads the right side of the car. I dont think the diff will change while turning seeing that it is cradled in the frame and has shafts.could be wrong tho. Anyone ever changed one out? any help would be appreciated.

[doubled87]

another note. it dissappears when turning right at speed or hard cornering.

[E92westy]

Well, on the commute this morning the noises have gone!
So cleaning / greasing the calipers & pads or adjusting the handbrake shoes seems to have worked.
Fingers crossed!!

[Dr Dave]

Happy Days! Thought that would sort it.

[Dr Dave]

Originally Posted by doubled87

another note. it dissappears when turning right at speed or hard cornering.

Sounds like a wheel bearing to me, quite straight-forward for a technician to diagnose which one.