Loud grinding noise when I brake.

JadeHighland

I drive a 10 year old Fiesta. When I brake, there is a loud noise like something is dragging under the car. Similar to have slightly flat tyres and mounting a curb.

I assumed it was the brake pads being worn, but what's a little weird is that it isn't all the time. I'll be driving the car no issue then after a while it will start making the noise when I brake. Any ideas? 

daveyjp

If you get a noise when you brake the first thing to do is have the brakes checked, not assume because its intermittent its not the brakes.  You could have a sticking caliper so the dodgy brake isn't operating correctly on each application,

Bigwheels1111

There are 100 reasons, rusty disc, pads low and brake wear indicator is catching.
Seized pad, a stone or bit of debris.
Can you see the pads through the wheel.
Are they worn out.

https://www.chapelhilltire.com/what-are-brake-wear-indicators/

Tucosalamanca

As already mentioned, as soon as you hear the noise, it's time to have the brakes checked. 
By continuing to drive you may have inadvertently damaged the disks as well.
Take it to the garage asap

Arunmor

My daughter moaned a month or so back that there was a noise coming from the back of her car.  I asked if it sounded as if it was metal on metal.  No I don't think so, was the reply.

20 yards I drove and the noise was awful, quick check showed deep grooves in the disc, was initially miffed that my mechanic had not mentioned it during the last service.  Turned out it was a sticky caliper so rear pads and discs all round and caliper sorted.

I just wish she had said something sooner as there was plenty life left in the disc.

Get to your local mechanic immediately sounds very similar.

Ganga

Arunmor said:

My daughter moaned a month or so back that there was a noise coming from the back of her car.  I asked if it sounded as if it was metal on metal.  No I don't think so, was the reply.

20 yards I drove and the noise was awful, quick check showed deep grooves in the disc, was initially miffed that my mechanic had not mentioned it during the last service.  Turned out it was a sticky caliper so rear pads and discs all round and caliper sorted.

I just wish she had said something sooner as there was plenty life left in the disc.

Get to your local mechanic immediately sounds very similar.

Disc,s are not expensive if bought from motor factors rather than main dealer.

Money_Grabber13579

I have what I would call a loud screeching/scrapping noise from my brakes, but only when almost stopped and braking gently.  The garage has told me twice now that there is nothing wrong but I’m not convinced.

Ectophile

Money_Grabber13579 said:

I have what I would call a loud screeching/scrapping noise from my brakes, but only when almost stopped and braking gently.  The garage has told me twice now that there is nothing wrong but I’m not convinced.

Might be cheap and nasty brake pads.  Or someone forgot to fit anti-squeal shims when reassembling the brakes.

Goudy

Most modern cars will have some sort of brake pad wear warnings on them.

Some have an electrical circuit that once the pads wears below a certain level, it makes contact and lights up a warning on the dash.

Or more commonly

An acoustic wear warning.
These are little metal tangs attached to the brake pads that touch the disc and make a scrapping or grinding sound once the pads wear down to a low enough level (2mm).

Brake pad wear indicator | HELLA PAGID

Brakes squeal is usually the brake pads vibrating in the brake caliper.
Brake dust and rust tend to cause the normal caliper movement to gum up and the pads start to shimmy with a high frequency and squeal.
A good clean up and a proper lube of the correct parts with brake grease (not normal grease, that burns) usually sorts it out.

You can sometimes hear brakes hum, particularly in reverse with rear discs.
Again it's rust and crud gumming them up but as the rear brakes only do 30% or so of the stopping, they don't get as hot as the fronts, so tend to show up these sorts of problems first.

My colleague has just walked in to the office as I'm writing this.
She's moaning her Yaris Hybrid had to have pads and disc all around yesterday.
The rears were original with 150k on them, but they hadn't worn away as much as rotted away!

JadeHighland

Turns out both brake pads were worn, along with there being a hole in the exhaust pipe. Nice £500 to fix it just before Christmas!

macman

JadeHighland said:

Turns out both brake pads were worn, along with there being a hole in the exhaust pipe. Nice £500 to fix it just before Christmas!

How much?
Who quoted you that?