What would cause this? Re: rear brakes

[Jim Bowen 1]

I'll try and keep it quick

 

Basically car has been making a grinding/rubbing/scrapping noise from the rear wheel

 

is very noticable at low speeds

 

took it to garage and they found that the face you don't see (inner side) of the passenger side rear disc is rusty where it should be shiny from the pad making contact, is just a small area on the outer edge of disc that isn't rusty (i tried to do a pic)

 

 

should i get new discs (other side is fine), could it be something suspension related?

[davidwort 0]

Not good, under heavy braking you could be getting far more braking from the other side of the car.

I would always replace both sides at the same time, so you'll be looking at new disks, pads and wheel bearings for both rears.

 

You also need to make sure that the caliper piston is free and winds back and pushes out (with pedal or hand brake) freely the full amount it needs to, for new to worn pads and disks.

[NickVR6 0]

bet its the calliper. fit mk4 rears they are tonnes better and a fraction of the weight!! can get a pair from a scrapy for £20-£30.

[Jim Bowen 1]

i had some new pads put on it about 4000miles ago, not sure if its anything to do with that

 

i have noticed a very slight knocking kinda noise from that side, can mainly hear it when in the car with windows shut

 

i should really try and fix some of these things myself rather than keep paying garage :(

[NickVR6 0]

where u based?

[Jim Bowen 1]

i am 5-10mins drive into the countryside from Stansted airport, i usually just take car to a local garage, but sometimes i feel as if they can't be bothered :(

[NickVR6 0]

bit far or id have a look. Fairly easy to unbolt the calliper and see if its seized though. should wind in and out fairly easy.

[Kevin Bacon 5]

That is very common. What happens is the pad binds in the caliper carrier and rusts on solid, and the caliper struggles to move it, hence the partially wiped disc.

 

Even new pads do this over winter IF, you or the garage don't file the carrier smooth and copper grease it, which is what David Wort touched on - the pad has to move freely or it will bind and not press onto the disc. They are small calipers at the back with little pressure, so don't have a lot of force to over come binding like the fronts have. And they also never get hot enough to burn off corrosion and dirt either, if you drive too slow :lol:

 

I've also seen brand new pads bind in clearanced carriers, so file them too.

 

Just a few minutes work during fitment to save you a whole pile of grief and cash further down the line.

[TomD 0]

Mine did a very similar thing but the other way around...rust on the outside. I changed the discs and pads and it sorted it out. :)

[Jim Bowen 1]

the noise has gone away now???, when i took it to garage they took it for a drive and couldn't hear it, but noticed the disc/rust.

 

i really have no clue about what to do to check the caliper out, i can take a wheel off :lol:

[TomD 0]

Its probably brake related, but it could also be the wheel bearings, mine had a knackered one when I bought it and made a nasty sound, more like a whirring though, but it did sometimes go away temproraily

 

Otherwise, it could be the strut top mount, or the rear beam mounting bushes. Or your exhaust kncoking on the underside of the car/rear beam.

 

 

I've just spent a shed load buying bits and peices to try and stop all the rattles, knocks and bangs on my C, but I don't think it'll ever be quiet and smooth! :cry:

[GIXXERUK 0]

I've just spent a shed load buying bits and peices to try and stop all the rattles, knocks and bangs on my C, but I don't think it'll ever be quiet and smooth!

 

buy some audioscape pods and some good components, these coupled with a sub was the only way i could quieten my c down :-)

[RobMulvey 0]

"Basically car has been making a grinding/rubbing/scrapping noise from the rear wheel"

 

"is very noticable at low speeds

 

"can mainly hear it when in the car with windows shut"

 

Hi,

 

I've had all the above symptoms and the noise also goes away if I slightly touch the breaks or slightly pull the handbrake. I also had my rear brake discs and pads changed anbout 1000 miles ago.

 

I was just wondering if you ever got a solution to this noise. Would also be grateful to anyone else who knows the answer.

 

Thanks,

 

Rob

[GIXXERUK 0]

this sounds like a wheel bearing , they will often change tone/sound with a change in direction , jack it up and check for play and spin the wheel to see if it runs smooth

[Jim Bowen 1]

i really think mine is a bearing now, the grinding noise stopped and was replaced with a high pitch squeal that goes away with braking or changing direction

[davidwort 0]

i really think mine is a bearing now, the grinding noise stopped and was replaced with a high pitch squeal that goes away with braking or changing direction

 

rear wheel bearing usually makes a groaning sound that gets noisier/quieter when changing direction as there are two bearing races, inner and outer, and it depends which one has the pitted surface.

[colinstubbs 0]

RobMulvey, if the bearings were changed with the new discs you can probably get away with tweaking them up just enough to remove the play, without replacing them.

[Jim Bowen 1]

i really think mine is a bearing now, the grinding noise stopped and was replaced with a high pitch squeal that goes away with braking or changing direction

 

rear wheel bearing usually makes a groaning sound that gets noisier/quieter when changing direction as there are two bearing races, inner and outer, and it depends which one has the pitted surface.

 

thats the other odd thing, this appears to be coming from the front, but i could be wrong :lol:

[davidwort 0]

thats the other odd thing, this appears to be coming from the front, but i could be wrong :lol:

 

can be difficult to pinpoint, those frequency sounds seem to travel through the body of the car, sometimes the only thing to do is investigate each bearing to see which one is visibly worn, very tiny pits can make quite loud noises too.

[RobMulvey 0]

colinstubbs, I didn't get the bearings changed with the new discs. Wish I had now!

My mechanic things my handbrake cable might be sticking due to water getting in through the liittle rubber boot which has split. I'm not convinced

[rosswalker 0]

It sounds like the wheel bearing. I had the exact same problem, killed my disc :(

 

I would be willing to bet that if you replaced the bearings then it will be all good, although your disc might need replacing as well.

 

- Ross

[colinstubbs 0]

I shouldn't think the discs would be affected at all to be honest.

 

Should be able to knock out the bearing races out with a hammer and drift/screwdriver. Put them back in with a socket and hammer or use a vice if you have one. Then it's case of finger tighten the hub/disc nut. Although i've found that they my need a tweek up a bit later so i tweek'em a tiny bit more just enough to guarentee they won't slacken. You can tell if they're too tight by rotating the wheel, you'll hear it! Use the wheel on to check for play too. There's probably something in the Knowledge Base I'd have thought.

[GIXXERUK 0]

you can put the bearing in by using the old casing

[colinstubbs 0]

Indeed yes. Luckily I had a mate with a lathe turn up two custom tools for nowt, it all helps!