[moseleyeve]

https://www.youtube.com/shorts/72hgn...ke7nJlITtmt_zO

I have a 21 plate 218i BMW Sports Tourer, purchased November last year. Over the past few weeks it has developed an intermittent rotational grinding noise from the back driver rear wheel but only when slow braking, so if I keep my foot on the brake a little longer than normal. Can hear in youtube video link


I have had it in two garages to check the brake system. Both have said the brakes are fine, plenty of life left. The second garage said the brakes are in very good condition, newish. So as far as they are concerned brakes aren't causing the noise. They did mention there was evidence of a stone maybe, one tiny scoring mark on the brake pad but not there now. They also said suspension springs etc looked okay. As with these things the couldn't hear the noise even on an extended test drive!!


Seems slightly better when warmer, and a bit worse if I've washed the car.


The noise is not too loud, not continuous, doesn't happen every time I slow brake but is still there occasionally. It cyclical with the wheel speed, so as I slow the noise slows, but its only evident as I'm almost at a standstill.


No reduction in brake performance, tyres seem fine with tread etc.


I have extended warranty on the car so is this something I should be pushing to be checked? Or is this "normal" brake noise. One garage suggested the brakes might still be bedding in?!
Many thanks for your help

[Rolebama]

There are a few reasons that could be causing that noise, from harmless to dangerous. Rust spot on the disk to cracked/warped disk. I have never heard of brakes bedding in making that noise, although I am not discounting this. Either way needs a proper check.

[moseleyeve]

@Rolebama thanks for the info. I've had the brakes checked twice in the last month or so, both garages advise they are fine. I went back yesterday with the video of the noise and they seem to agree due to the cyclical nature of the sound and it happens when I apply the brakes its something not visible to the naked eye ie warped disc. I am booked in to have them replaced now

[NMNeil]

I listened to the noise and my truck had a similar noise but from the front drivers side, ended up being the wheel bearing which just like the BMW is sealed.
Jack up the rear of the car and make sure it's safe. Grab the tyre top and bottom (12 o'clock and 6 o'clock) and see if you get any movement. Now repeat for the 3 an 9 o'clock position. If you feel movement or hear any clicking, change the bearing.

[moseleyeve]

@NMNeil - thanks for the advice. I'll check that

[moseleyeve]

Originally Posted by moseleyeve

@NMNeil - thanks for the advice. I'll check that

could I just ask if the sound you heard from your truck was only when slowing down and intermittent?? Many thanks

[NMNeil]

It got louder when a load was put on the wheel, such as turning, but it mostly made a droning noise punctuated with a slight clicking. All the noises were dependent on speed.
Difficult to describe from memory.

[TyreRunner]

@moseleyeve It could still be light surface rust, a bit of trapped grit, or even a slightly uneven wear pattern on the tyre that only shows up under low-speed braking. If it’s worse after washing the car and better when it’s warm, moisture might be exaggerating something minor.


Since you’ve got extended warranty, definitely worth pushing for it to be logged properly. In the meantime, this quick tyre check guide might help spot anything the garage overlooked: How to replace a car tyre – what to check first. Hope you get it sorted soon!