Brake binding and disc warped - cold weather or coinkydink?

[Bobby Dazzler]

Parked the C32 on the drive way on Christmas Eve in a few inches of snow, having driven 10.5 very steady miles without touching the brakes much at all. It's stood there until this morning, so 10 days in total.

I covered about 120 miles in the week before Christmas, and I'd been very light on the brakes due to the snow and ice. Car performed beautifully.

This morning though, the car didn't creep forward in Drive, a light press of the accelerator prompted a sudden release, but then the brakes sounded noisy as I progressed along the drive way.

Not to worry, I thought it was perhaps just a little surface corrosion due to the weather we've had of late, and it'll wear off. It hasn't cleared though, and the disc is clearly warped.

There was frost on the screen but 1.5 degrees C so unlikely anything was frozen hard.

A quick inspection in the dark and rain shows some peculiar marking on the NSF disc which I think is where the pad sat whilst parked, and which is now being worn more aggressively.

Anyone else experienced similar problems after being laid-up in the snow?

Maybe the caliper was sticky, and caused the disc to overheat, and nothing to do with the weather. Maybe the snow caused something to freeze. Maybe the damp weather caused more surface rust and fused the pad to the disc.

I also read that brake fluid can oxidise (made worse in cold weather) and cause sticking.

The discs and pads were changed by the main dealer in December 2006, but I could see there was plenty of life in the pads when the wheels were removed in November for new tyres. The fluid was changed by the main dealer in September 2009, so fairly fresh.

What does the MBClub collective make of it?

 

[corned]

This is mere speculation and hypothesis, but here goes anyway...

My guess is that the car has stood with a layer of moisture between the brake pad and disc surface. This has festered more than usual because of a. salt-ridden moisture, b. the brakes not getting hot enough to properly evaporate off the moisture, and c. the car then standing like that for a number of days. No coinkydink!

You may be lucky, and a few miles put on with some spirited braking may reduce the effect of the uneven patch, but the sooner this is tried the better.

It may take a few days to wear off, but unless the situation is particularly dire I would expect the brakes to be able to 'recover' from this.

 

[Will]

Is it possible that in the week leading up to when the car was parked up, the severe cold weather (ice/snow/freezing conditions) could have caused the caliper to freeze up and seize? Maybe then causing uneven deposits of brake pad material onto the disc or perhaps warping just before you stopped using it.

Will

 

[jaymanek]

We get this all the time with the amount of cars we have sat outside.. I would monitor it for a few days and it may clear... If the discs is definately warped then not much else can be done... when changing the fitter will know if the caliper has seized or not.

 

[Bobby Dazzler]

Thanks Gents. I used Mrs Ds car to be sure, but I'll try it again tomorrow, and if no better, get the new parts ordered.

 

[paulrstaylor]

I reckon its likely to be a pad/rust deposit on the disk, a few days of use should clear it off and have your disks back to normal!

 

[Rory]

I often don't use my car for weeks at a time and the disks look terrible - I took it out the other day for the first time since all the snow and it moved off with a terrific clunk as the pads released. But a few heavy stops and the disks looked fine when I got home.

One thing I always try and do is ease the brakes off as I come to halt - it's said that if the disks are hot then some of the pad surface can transfer to the disk and this has the effect of making the disk feel like it's warped. Ideally for brake cleaning you shouldn't actually come to a halt, but it's had to find roads where you can repeatedly speed up and brake without annoying other road users.

 

[Bobby Dazzler]

This morning vibration seemed better than previously so hoped it was getting better. Did quite a few progressive stops but getting worse again rather than better. New discs and pads about to be ordered...

 

[Londonscottish]

But are you sure you mean you thought you might have had a coinkydink?

I just looked it up on the Urban Dictionary and the definition is....err....not exactly car-related shall we say.....

 

[Bobby Dazzler]

Err, I'm nervous as to what it might mean now!!

I can't really look whilst at work either if it's unsavoury!!

 

[davidjpowell]

There are two definitions by the look of it. You are right in that you probably do not want to look at the Urban Dictionary version whilst at work.

 

[grober]

In this sub zero temperature period after starting off its always a good idea to run a short distance with the brake pedal lightly applied- this can be done with gentle left foot braking on an automatic. This has the effect of warming up the brakes--discs +calipers so come the time you really need them to work they are up to working temperature. Warmed brakes will also help evaporate off any moisture when you come to a halt and park up.

 

[davidjpowell]

Hmm. next time the car does not want to move I think it will be a breakdown call. £177 for new pads and front discs + fitting not fun in early Jan.

 

[Londonscottish]

Err, I'm nervous as to what it might mean now!!

I can't really look whilst at work either if it's unsavoury!!

No. Don't.

(do have a look when you get home though......... )

 

[Bobby Dazzler]

Parts ordered. Noticed pedal seemed soft tonight. Hopefully just because I'm focussing on the pedal feel now due to the vibration, and nothing else.

Urban dictionary now checked. Ahem.

I've used that word for years too, having heard it on Renn & Stimpy!!...

 

[kit17]

My C320 did something similar after the christmas break, but after 4 days of commuting and 250 miles its now fine. My discs have done just over 59K so will probably need changing soon anyway.

 

[Neiltodd]

Mine was the same last year but some firm use of the brakes over a couple of hundred miles & back to normal,so far this year ok.

 

[Bobby Dazzler]

A week's use (around 100 miles) didn't see any improvement, and so I went ahead and had the discs and pads replaced all round today.

Once removed it was clear to see that the old discs had marks on them where the pads had sat, most probably due to corrosion of the pad on the disc face.

There was still plenty of life left in the discs and pads which is a shame. I think the rear pads were still originals - which is incredible as the car's now more than 7 years old - so not such a bad thing replacing them now.

Vibration now gone, and normal service resumed!!

 

[moonloops]

Parts ordered. Noticed pedal seemed soft tonight. Hopefully just because I'm focussing on the pedal feel now due to the vibration, and nothing else.

Urban dictionary now checked. Ahem.

I've used that word for years too, having heard it on Renn & Stimpy!!...

Some people think coinkydink is slang/short for coincidence :lol: