[marklemac]

Hi chaps,

After some advice please.

My other halfs car (2008, E92 325d coupe).

Now prior to this we had no droning noises with the car.

Had an issue whereby the rear right caliper was sticking so we had this replaced.
At the same time we had new rear discs and pads fitted too.

Since this, we were getting droning noises at around 60mph.

We've had the wheels re-balanced and swapped over and the drone is still there.


Could this be linked to the work done, or maybe just a co-incedence and it might be the bearing ?

I know the bearing is an expensive job (especially if it's stubbon to get out), don't want to shell out for that to only find the drone is still there?

Does that make sense ?

Any advice welcome

[adammcf]

Its possible the heat from the sticking caliper has damaged the bearing in that wheel. If you jack the rear up and rotate that wheel by hand see if you can feel or hear anything.

[Phil325i]

I have three suggestions, based on past experience:

1. Corrosion on the inner face of the disc (the face you can't see)
2. Diff on the way out
3. Mis-formed or uneven tyre wear.

[marklemac]

Originally Posted by adammcf

Its possible the heat from the sticking caliper has damaged the bearing in that wheel. If you jack the rear up and rotate that wheel by hand see if you can feel or hear anything.

I did wonder whether the heat could have damaged the bearing ?

The car was driven for around 10 days in this condition until we could get the caliper replaced.

I will jack it up and give that a go thanks.

[marklemac]

Originally Posted by Phil325i

I have three suggestions, based on past experience:

1. Corrosion on the inner face of the disc (the face you can't see)
2. Diff on the way out
3. Mis-formed or uneven tyre wear.

The disc is brand new.

Wheel has been swapped to the other side and noise remains on the drivers side.

It is a 'rotational' sound.

[Phil325i]

Then I would say wheel bearing or driveshaft.

[creepy coupe]

Q the mother-in- law jokes.

[old grey steve]

Could be anything really but to pick up on Phil's 3 observation feathered tyres aren't unheard of they'll usually feather on their inner edges eventually this will go to the next level where the treads worn through and there's bare rubber and then from there rather quickly you'll expose cords/canvas you'll sometimes get as you have described a kind of droning noise from the rear not unlike a wheel bearing but the easiest way is to have the car in the air and inspect those inner edges but as said may not be this but its worth a good look.

Diffs on these are usually hard wearing well better than that offered on the 4 cylinder units likewise the drive shafts are better too but the only way forward is to have a good look.

[ChawenHalo]

Originally Posted by Phil325i

Then I would say wheel bearing or driveshaft.

+1 I'd put my money on Wheel bearing too. Its odd that it should happen right after the garage sorted out the brake caliper. Bring it back to them. It may be Something simple they've not tightened up correctly.

[old grey steve]

Having re read the OP's question re tyres still say these if feathered can produce droning type issues, but pre work OP's not stated there were any issue's so having read the question only very briefly while at work yes tyres can drone if feathered but looking now at the question again the issue as stated centers on the rear discs and pads post fitting.

With the new discs and pads fitted working as I do in a garage if applied correctly there really shouldn't be any great need to stress the bearing assembly at all to be honest when you are re fitting the brakes it should be a straight off/on application, re the seized caliper yes this is common, calipers can seize for more than one reason but replacing the caliper bleeding the system and replacing the discs and pads will usually see you right.

The one thing I have seen before in fact a fair few times is with the hand brake itself when tackling a brake replacement or even the dust plates at the rear.

When or if the shoes are adjusted and not done right at speed heat build up, metal expands can if these have been incorrectly adjusted then yes there could be a fair chance that the shoes could just could be coming in to play likewise if the old shoes are re use and have started to de-bond for instance if again adjusted and done so the hand brake is to tight as speed builds up there is a chance these could again come in to play (bind) for instance likewise if the dust plate has been disturbed or has even started to corroded from the centre then these can play up too.

Mere fact that it is a rotational sound could of course open a fair few options yes the noise you're hearing could be wheel bearing related or drive shaft (but to compromise this in my opinion after a brake replacement you'd have to be damn unlucky, the bearing was already on its way if it was a bearing noise, hammer and spanner done the brakes and done something really dumb) my reasoning for this is why would you compromise bearings and drive shafts when simply changing disc and pads.

Might be worth on the brakes looking at perhaps the hand brake set up to see if post work they are partially binding back te hand brake off a bit and see if this works and at the same time perhaps see what the state of play is re the back plate. Seen hand brake issues due to incorrect adjustment may a time before and simply backing the effect off a little can help, likewise seen disturbed back plates create the odd issue too

[bfleming]

Diffs can run dry. Look for signs of oil leakage (takes 5 seconds to look under the car from the rear).
But, like the others, I think wheel bearing. Hypothetically a sticking caliper can heat everything up at the hub, so it could be related (10 days driving like this is mechanical stress personified).
Does your handbrake work effectively?
How much tread is left on the tyres? Running them down to the wear markers will cause a droning / vibration.
Keep us posted.

[Russbmw]

Has been mentioned above, but worth reiterating....

Before you start freaking yourself out about buggered diffs or shagged wheel bearings, check your tyres.

What brand are they?

Even if they're not feathered on the edges, if they're getting close to the wear markers, some tyres can start making a right old racket.

I had some continentals on an old e39 years ago, and I could've sworn blind a wheel bearing was shot, it was that exact same noise, and started becoming apparent at about 50mph. As it happened, changed the tyres as they were getting low (not down to the wear markers at the time, maybe 2mm off). New tyres = no noise.

I also had the rear shoes on an e46 just fall off their carriers and jam in between the metal bit of the brake shoe and the inside of the drum, and so were merrily rubbing away for God knows how long - could easily have been a week. At one point my rear wheel was hot enough to generate steam when I cleaned the car one day just after I got home (which was how I was then aware there was a problem).

FWIW, I wouldn't have thought heat would damage the bearings. It's not like the grease in bearings is water and evaportates if it gets hot!

[apollo]

Does the noise increase or decrease when cornering? as this usually indicates a bearing. I had this recently myself where when the bad bearing was loaded the noise went away which is actually the opposite of what normally happens as I believe the bad bearing normally gets louder when loaded. It cost me £150 to have it replace including new F.A.G bearing

[marklemac]

Got the car booked in next week for the work done to be rechecked.

Tyres are new, no wear on them. I have swapped the wheels over just to double check.

I can't check the noise when cornering as the noise only really starts at 50/60 mph upwards,

Hopefully I'll have more of an answer next week.