Grinding noise front left alloy.

[GlennNich]

Just had a new tire on the front left and the car is making an awful grinding kind of noise from the alloy. It was MOt'ed three days ago so can't be the brake pads surely?

Any advice appreciated.

Glenn.

[snapdragon]

Brake pads are not tested in the MOT, they just check the brakes work efficiently on the rollers. Check the wheel bolts, and if they are OK, take the wheel off and check that the splash guard wasn't bent by the tyre fitter which can make it rub on the edge of the disc (or take it back and let them check).

[martin1810]

My money is on a stone caught between the splash guard and the disc or the guard is bent as snapdragon says.

[venetian-red]

Could well be worn pads because I bought a Passat 130tdi estate which had an MOT put on it that morning and had a grinding noise within hours.....which was totally worn rear pads!

[martin1810]

A good MOT tester will advise on the state of discs and pads. I guess they don't all bother.

[GlennNich]

Thanks for all the replies. I'am by no means an expert, however the noise occurs only when the brake is NOT being used. This leads me to believe it's not the brakes.

Is there an easy way to see the splash guard or do i need to get under the car.

[martin1810]

The easiest way to check the splash guard is to take off the wheel and turn the disc by hand. You can listen and look at the same time then.

[Panzerdriver]

Have a look at the balance weights. Did they use the stick on types if so make sure they are not contacting the brake caliper.

Had the very same problem on my wife's Polo only sussed it when i found witness marks on the weights.

The strip had been put on over a lip on the rim about 1.5 mm high but it was enough.

[GlennNich]

Have a look at the balance weights. Did they use the stick on types if so make sure they are not contacting the brake caliper.

Had the very same problem on my wife's Polo only sussed it when i found witness marks on the weights.

The strip had been put on over a lip on the rim about 1.5 mm high but it was enough.


I will have a look at this first thing in the morning. Makes perfect sense. Cheers. :biglaugh:

[Panzerdriver]

Hey Glenn any joy with your mystery noise??? or has it faded away.

[GlennNich]

No joy I'm afraid. Checked the tyre but can't see anything that may be making the noise. One thing I have noticed is it only seems to make the noise when wet, I sprayed it with wd40 to remove the moisture and it disappeared for a few hours.

Very strange.

[burnleywhite]

Hi all, just found this thread. Last week I changed the rear pads and the front pads/discs. All went tickity boo (eventually) and everything works fine. After a day or so I noticed a grinding noise coming from the front end, I thought grit or summat trapped between pad/disc, but it's not going away.
I did notice a couple of flat lead pieces on back street where I did brakes, but it's a typical northern back street with car rubbish. I also noticed 'clean' parts on my alloy inners where it looked like something had dropped off. Balance did cross my mind, this thread sort of confirms it, cheers all.:beerchug:

[burnleywhite]

Just checked the brakes again, quick look through alloys,and it looks odd. There is road dirt on bottom two thirds of disc (from hub up) and only the other third is 'clean'.

Surely there is more pad/disc contact than that? Brakes work fine, car stops spot on, no jarring, just this intermittent grinding sound.

I was surprised, on changing the discs, just how little the disc leaves on the hub for the roadwheel to sit on. Bit of a pig to do the bolts and hold the wheel in situ at the same time. I was wondering if, due to this, it's possible that the disc has slipped a tad and the whole shebang is now tight but slightly off centre?

There again, what are the chances of doing that on both sides?

[b197ony]

ive recently had this problem on my b5 and it was the disc running off centre and just clipping the inside of the caliper i only found this out as i was going to strip and clean the caliper thinking it was sticking on the sliders
i also noticed theres no locating lugs or screws on my hubs which seems strange as every other car ive had has had the locating screw to hold the disc in place
all i did was apply copper slip to the inside of the disc where it meets the hub and then wound a couple of wheel bolts in until they was tight then removed the bolts and refitted the wheel and the problem seems to be cured for now

[burnleywhite]

Cheers for that. I thought it was funny that there was no grub screw or the like to hold the disc in place.

Sorted mine now, what a muppet! The spring that holds the front pad in place was on wrong. I'd put it on OVER the lugs, rather than under them. It was only when I had stripped, greased, and was putting it all together again that I realised what I'd done.

All sorted now, and nice quiet motoring is resumed. :beerchug:

[b197ony]

glad you got it sorted easily:D
i wonder why they didnt make them with locating screws as my discs have quite a bit of movement on the hub making a wheel change a real chore:(

[burnleywhite]

Aye, it's one of those jobs where two hands isn't just enough to do it easily.

German technology and efficiency I reckon. :D