Driving with dragging brakes

Gwynston

Our 2008 S-Max has recently had an intermittent problem with the ABS sensor - the light would sometimes come on by itself and when pulling off, you could feel the ABS trying to kick in. But the issue would go away after getting going.

So when I had it serviced last month I got our Ford dealer to look at it and they found some "fault codes logged for the OSF wheel speed signal" and concluded it was a "possible wiring fault". However as they would "need to strip out to investigate further" it couldn't be done on the day of the service and would need to be booked back in.

Anyway, it wasn't causing much of an issue and we waited until after the Christmas break to do anything about it, and in fact for a couple of weeks it didn't reoccur. But now over the past few days, I can feel the brake dragging, even without any ABS warning light. It gets worse the further I drive and the right-front brake caliper and disc gets extremely hot.

I've only driven about 10 miles each way to work and back the past couple of days, but I'm wondering what I should do? I've booked it in again (and the dealer has warned me that it will cost a lot as they will charge for x hours of labour to strip it all down, probably over multiple days), but they can't take me until Feb 4th.

So what should I do for the next 2 weeks?

biko

Get a second opinion. Possibly the caliper pins needs lubing and an indie can sort it.

dr.fuzzenstein

Offside Front wheel speed signal. That would occur if the wheel is not turning when all others are (extremely unlikely except on a rolling road) or if the wheel speed sensor doesn't recognise it's turning (happened to me). So faulty sensor or faulty wiring could cause that. It should not cause the ABS to kick in, because once you have an ABS warning light, the ABS is disabled. Don't worry, other than that your brakes will function as normal.
So if you feel dragging or something else wrong with the brake, especially a wheel getting hot, it looks like a separate issue.
Going to a Ford dealer with this can get very expensive, very fast and you are better off with a good independent mechanic. Whereabouts are you located, OP?

Keep_Her_Lit

OP, I'm open to correction here but as far as I know, there is no mechanism by which ABS can apply the brakes, even under fault conditions. ABS operates by intermittently releasing the brakes at a fairly high frequency (many times per second) under defined conditions, e.g. when a skid would otherwise occur.

I've had sticking calipers on two cars in recent years and the dragging/overheating symptoms sound similar to yours. If that's the source of your problems, a thorough clean up, including new seals and boots may sort it. If the piston surface is damaged due to ingress of grit or other contaminants, that will need to be replaced, though it may be simpler at that point to replace the complete caliper with a new or reconditioned unit. The latter are readily available on-line.

If it's a sticking caliper, be aware that it can become extremely dangerous, so you need to get it sorted ASAP. The overheating brake can become almost completely ineffective, causing the car to pull dramatically to one side under anything but the mildest braking. The excess heat can incinerate the affected brake pads, turning them into useless ash. If you really can't avoid driving the car while waiting for the repair, keep your speed low (higher speeds generate more heat), increase your braking distance and stay off motorways.

Cee-Jay-Cee

Sounds very much like a sticking calliper and any able mechanic can free them up quite easily, you do not need to go to a main dealer who quite frankly are generally useless with problems that their diagnostics doesn't pick up.

Drive as little as possible as you will warp the disc if it gets very hot. The pads will also be wearing although new pads aren't expensive.

If your anyway mechanically minded you can do it yourself. Remove wheel, undo bottom calliper bolt (usually 12 or 14mm) swing the calliper up out if the way and tie it up something to hold it up. Remove the pads and start the engine and pump the brake pedal once or twice to move the piston outwards and free it. If the pads are new then the piston will be wound in almost fully so pump the brakes 3 or 4 times to bring it out further. Then get a small pick or screw driver and pry up the piston rubber boot and spray in a good dose of rustola to remove any corrosion. Then pry out the bottom of the rubber boot to allow it to drain out. Then get spray copper grease or white lithium grease and spray in a little under the boot. Wind/press the calliper back in again, refit the pads and calliper and wheel. Start engine again and pump Brahe pedal till it goes hard and take the car for a short drive to see if it freed it up.

Gwynston

Keep_Her_Lit wrote: »

If it's a sticking caliper, be aware that it can become extremely dangerous, so you need to get it sorted ASAP. The overheating brake can become almost completely ineffective, causing the car to pull dramatically to one side under anything but the mildest braking. The excess heat can incinerate the affected brake pads, turning them into useless ash. If you really can't avoid driving the car while waiting for the repair, keep your speed low (higher speeds generate more heat), increase your braking distance and stay off motorways.

This is not what I wanted to hear.... :eek:
Once it all heats up, the brakes don't feel normal, alright. And even freewheeling, there seems a bit of a judder. I hope the disc isn't warped already...

I live outside Galway and work in the city. Can anyone recommend a good independent mechanic, or should I post on Regional?

I have been taking it very easy. Keeping speed down, no hard braking etc. But I can't help thinking I shouldn't be driving the car at all...

ohnonotgmail

If you feel a judder and the car pulls to one side when you are braking then you have already warped the disc.

Mech1

Do not under any circumstances do what cjc advises. No Rustola or copper grease please.

Cee-Jay-Cee

Mech1 wrote: »

Do not under any circumstances do what cjc advises. No Rustola or copper grease please.

I apologise if I gave any incorrect advice but it worked for me roughly 3 years ago and hasn't given bother since (approx 50k kms)

Gwynston

I stopped by a mechanic on the way home and he says he can take it in to fix it Monday morning, but I shouldn't drive it in the meantime.

I'm kind of afraid the disc might already be warped though, and he told me if it needs replacing, they should really done in pairs.
He'll still probably work out a lot cheaper than the Ford garage, though...

Boskowski

There is a good chance the disc(s) are gone too at this point but they're not THAT expensive. It all adds up of course but were not talking a fortune here for two new discs. A quick look on eBay shows anything between 50 and 100 Euro for the pair depending on quality and make and that may include new pads even, so about double that I'd say when coming from a mechanic.

Gwynston

So the diagnosis this morning is as follows:

The caliper, pads and sensor all need replacing. And the discs are warped on both sides! (Not sure how that happened on the other side?)

Anyway, he has all the parts in stock, so is fixing it all today. (Is it usual for a small independent garage to have such stuff in stock for a Ford S-Max? Not exactly a common model)

The only think he has to order is the connecting wire for the sensor, but he says he'll finish everything else today and let me take it home. Then the wire can be fitted as I wait tomorrow.

Mech1

You will find that the local motor factor is the one who has them in stock.

Gwynston

Oh yeah, I suppose they use the local supply network.

Just collected the car and he got everything done today. He ended up repairing the connector wire himself because a replacement was going to cost €120!

Got it all done for €550, which isn't bad as he did have to replace quite a lot. I'm sure it's a lot less than the Ford dealer would have been and I'm just happy not to have to lose the car for days.

The brakes don't seem that strong in the short drive I've had. I guess completely new front discs and pads need a bit of bedding in?

Boskowski

Thats right.