[Closed] Weird van brake disc failure

Nope but at that age/mileage I’d be chasing a warranty repair.

However they may say 30k is more than acceptable for discs so be prepared for a fight.

What van? As most I know of will cover 50+k before needing new discs through wear not a web failure.

That is very interesting.

Could it possibly be a manufacturing failure with the disk?

In my head that also could be one pad having much more friction than the other. What do the pads look like and is piston & mechanism free moving?

I would have thought the ribs would be more than up to dealing with the maximum braking force from the pads.

I'd be on the phone to the manufacturer, both to make them aware of a failure in the brakes and to see if they'll cover the costs if the van has any warranty. Because unless the brakes turn out to be worn in some unusual way then that really shouldn't be happening to say the least!

Although 3 years old? Has it had its first MOT? If not the disks might have been worn/cracked and you didn't check? The previous owner managed to do more wear to my cars brakes in 30k than I did in the next 90k! A good reason not to trust "one retired lady owner"!

I'd be expecting a decent explanation and warranty on that. If not, I'd be getting DVSA involved - they don't tend to like sudden premature failure of safety critical parts.

Have seen sticky sliders causing more extreme wear on one side and weakening it but never a separation of a good thickness side. The vanes in the middle are normally pretty substantial.

30k is not unreasonable to wear out a set of discs though in the right conditions. Our Freelander eats brakes despite never going particularly fast as it's an auto, tows a lot and gets used for short commutes. I normally replace pads every year but for some reason the current discs will be getting swapped with the first pad change this year. Will be replacing the sliders again...

What van is it? If its French good luck with getting any joy from them.

Thanks for all the thoughts so far.

I am suspending judgement until I have been able to inspect the disc / pads personally and speak with the dealer mechanics. The disc is nowhere near worn out, lots of thickness on the friction surfaces, just broken in the middle.

I will indeed be looking for a good explanation and will involve the manufacturer / regulator if needed.

The van is a Ford Transit Custom so nothing to worry the STW T5 camper crowd :-).

There's all sorts of things that could contribute to the failure (corrosion contributing to accelerated fatigue failure etc.) but for that to happen the disc wasn't up to the job anyway. <span style="font-size: 0.8rem;">(Bear in mind the vanes would be expected to take half of the braking torque anyway)</span>

It could be all manner of things- porosity or a duff casting with bits missing, impurities getting into the metal - but for something like that, it's something I'd expect warrantied and investigated properly by the manufacturer.

A less than sympathetic driver could get trough a set of pads in under 30k miles and these days is fairly normal to change disks and pads at the same time.  If he's done the pads and you've had metal on metal then that'll overheat the disk and cause cracking which causes this kind of failure.

Might be a seized caliper as well perhaps?

A disk only needs to loose 1mm each side typically to be worn out.  The minimum thickness should stamped on the disk.

what about thermal shock adding to an already poor cast disc?

If you are able to tear yourselves away from the EU referendum thread, I have worked out how to upload photos of my crippled van :-(.

Thanks to all those who have replied, I will see what I see when the hub comes off the van.

I drive in a very lazy fashion, boy racer days are long behind me...

A mate had a disc break up on a MG Midget. It was solid I think, so it it fell on to the road and we veered towards the hedge!

not deliberate I promise.

Well, well, well.

I had the exact same failure 2 months ago. Thankfully before our alps trip.

2014 Transit Custom.

My mechanic says its 2nd time in 22 years he has seen it.

edit. Genuine Ford part BTW. 45k on them.

That's got to be a manufacturing fault, surely? I can't think of any other explanation for it.

The only time a disk should ever fail is if its been worn down way past reccomded thickness, and this doesn't look like that, it looks like a structural failure.

It’s 40yrs since I left/gave up the “trade” I worked on Fords for 2yrs and the discs were crap then, so nothing has changed it would seem......

I don't exactly follow what happened but my thought was side loading on the disk from a non centering caliper. Is the wear on both pads the same and are the caliper slides free.

(Haven't read all the responses don't know if this is covered)

I don’t exactly follow what happened but my thought was side loading on the disk from a non centering caliper. Is the wear on both pads the same and are the caliper slides free.

I see your train of thought but that theory should just result in a severely worn pad on one side, by design pads can't be able to cause damage to a disk in this way.. The pad material is more sacrificial than the brake disk, as a structural failure of the disk could be catastrophic.

That disc looks rotten. Have you been taking it for dips on the beach?

I disagree Mattyfez, but won't fall out with you until I set up a full scientific lab test. A calliper acting on one side of a disc will cause cyclical loadings orthogonal to the plane of rotation that could eventually lead to a failure. Your phrase "by design" seems lazy, please feel free to expand, I may revisit the thread later.

In summary I judge your response to be low quality.

/passive aggressive mode off

This happened to a work colleague of mine. He ran an old 944, probably 20 years old at the time. One of his rear brakes started making a strange noise with a strange vibration and in a similar way his disk had failed across each of the internal disc vented webs. I can only think it is due to corrosion thinning the webs out, I suspect the disc had been on the car for some time so looked similarly corroded as the picture above. The webs are probably under alot of stress as the disk part will cool alot more quickly than the hub part so you're going to get alot of shear stresses and if the webs thin out due to corrosion then that could result in fracture...it will only take one or two webs to fail and the resulting stress increase in the remaining webs will soon unzip them all the way around the disk. That's my hypothesis anyway. Pretty rare though.

Looks to me like a very worn and rusty disc.  Lots of other evidence of corrosion a well.  Was the van properly serviced by a main dealer?  They should have picked up the worn and corroded disc

Mattyfez - of course pads wear discs - otherwise a disc would never wear and lose thickness.

From what I understand, discs are almost considered consumables these days, I’ve never done more than 5k per year in my Octavia, yet I’ve had to replace a set of discs and pads every couple of years, the corrosion around the edges looked remarkably like those pics just before the discs were replaced.

I've had discs in far "worse" shape than that, once you take a wire brush to them (or a sharp pointy thing) you will realise most of that crap is brake dust. Once it's cleaned off the rest is solid.

Odd how the outside and the inside parts of the braking surfaces are different colours, almost like the outer has got hotter than the inner part.

"From what I understand, discs are almost considered consumables these days, I’ve never done more than 5k per year in my Octavia, yet I’ve had to replace a set of discs and pads every couple of years, "

this is not a correct observation - all it really says is youd probably be better hiring a car than owning one

to be fair to those saying its rotten

they are in a fair battered shape for 3 years old..... even the suspension componants etc look corroded to **** - and while i understand most of it is surface corrosion - theres no smoke without fire..

our berlingos disks at the same age look very very different to those - all shiny and still painted.

i see fords coatings are still up to spec 😉

Discs are considered consumables.  Especially if you use sintered pads you will need to replace your discs every 3 sets of pads or there about.  Discs wear!

not in 10k Tj . not unless your last names button , vettel , mcrae or burns.

The problem with 5k/year is that they will get more corroded as you're not running it often enough to clean off the corrosion, so you get a lot more buildup eventually eating into the braking surface.

Brake discs are made of cast iron, they do rust, the example in the pic isn't unusually rusty and I can't see a lip on it, however the different colours of each side is a bit strange. Could be a sticky caliper heating one side up at a guess, but if your pad wear is identical that would seem to disagree...

I am following this with interest as the brakes on my UK car used to last 30-40k miles but the ones I had in a drier but more humid environment lasted 140k with roughly the same type of driving. 70-150k seemed to be standard for the region.

i am more gentle on cars now and new materials are better but t that is a hell of a difference. Maybe the salting of the roads makes a difference?

Cornholio without doubt corrosion cracking and a warm salty brine is going to accelerate deterioration. Of material. Not so much wearbut shortens useful life . ... But not to 10k

where is 10k coming from? The op has done 30k.

are those pics a bit small for everyone else?

It does look like you are suffering from a lot of corrosion, do you live by the sea? Have you had a lot of gritting going on the last few winters?

Had a word with the missus last week about washing her car more often after I had to replace rusty brake lines to get it through it's MOT. The car is suffering a lot of rot underneath as it is never gets all the crud washed off. Also never gets cleaned out inside either. It gets used for towing our sheep trailer and for her short commute. When we replace it the new 4x4 will be getting a thorough wash and then regular coatings of a sheep lanolin trailer protection spray.

its 30 000 miles tho.  not 10 000.  I wonder what the inspection interval for checking discs is.  I know my BMW motorcycle had "check disc thickness" at EVERY service and replace after x years x miles regardless.

"where is 10k coming from? The op has done 30k." The rest of the discussion below where someone suggested that he replaces his disks every 10k and this is a normal lifespan.

I'd be surprised if you got anywhere with warranty, brake discs will probably be firmly in the consumables camp especially after 30k miles of use. They might come to the party with a goodwill gesture but I wouldn't be holding my breath.

We had an issue with wheel bearings after 40k, even the dealer said it was a joke that they needed replacing so soon but warranty wouldn't touch it so was put down to dealer goodwill.

misread trailrat.  replace discs after every 3 sets of pads is normal is it not?  set of pads every 10 000 miles is not unreasonable is it?

Set of front pads in a lightly loaded / driven van would probably manage at least 40 thousand miles. Discs probably double that.

So..on the 10k issue the problem is likely that you are allowing the brakes to get rusty between uses. A disc that is allowed to rust up quite often is going to wear out quicker and wear the pads quicker.

Also the quality of the parts play a big role. My estate came with Mintex pads and discs (brand new) from the garage that sold it. The independent who fixed some things on it for when I got it commented that they were "cheap" as they tend to fit genuine parts only (or know the OEM make). I am very particular myself with car parts and either buy parts and filters from the dealer or from the OEM who makes them most of the time but for brakes I have been using Pagid from ECP. Not had great wear out of the Pagids on the landy and the Merc is going to need both pads and discs after 18 months (20k) so switching the landy to Brembo discs and pads this time and possibly the same on the Merc. Not looked at prices yet, will need to sit down I suspect. I have used Mintex previously on my 306 and never had anything bad to say.

just looked at discs for mine and spotted they also have vented rear discs at £100 each. Clicked more details and it says "Special usage for armoured vehicles" - cool!

Fronts are not too bad, £90 before the usual ECP discount to bring it down to the same price as others (about £55-60 each). Looks like ATE are OEM for merc. Worth finding out who Ford use..and then avoid them by the looks of it!

Set of front pads in a lightly loaded / driven van would probably manage at least 40 thousand miles. Discs probably double that.

To date my car's done a bit over 50k, rear discs and pads had to be replaced (less heat in them, rust more of a problem, although I think the pads were quite worn). The front discs and pads are originals. I drive quite hard, and it used to get used around town all the time by the ex.

I don't think the front discs have much life in them, they were showing some signs of being a bit warped when hot (descending steep things in the Lake District) a few months back, but still it's quite possible the OP's were not very worn after 30k miles, and they don't look badly worn from what you can see on the pics.

10k is crap, but believable if you have salty roads etc. to deal with and it ends up sat around a lot of the time.

3 sets of pads is normal is it not? set of pads every 10 000 miles is not unreasonable is it?

3 sets of pads sounds about right. 10k to a set does not!

Think I've got easily 30k out my Mondeo on a set of pads, perhaps more, I'll need to check. If I've not changed them then it's over 40k. If your pads are wearing out that fast you either need to improve your driving technique or something is wearing them out fast (my back ones are just about down to the metal on one side of each pair after one handbrake cable outer popped and the other caliper jammed closed).

Need to measure the discs and see if they need done as well, was thinking Bosch would be a good bet.

Seemingly Ford OE parts are [url= https://talkford.com/community/topic/277066-pagid-brembo-eicher-or-mintex-brakes/ ]ATE[/URL] or else Bosch if original caliper. Also worth noting that only applies to original spec equipment and not Motorcrap which dealers have been known to sell as OE. Motorcraft IS a Ford brand but basically a farmed out product to be used on older models to keep costs down. If you can sell it as Ford then margins are higher.

Surely not all vehicles load the discs equally? A lightweight one will keep them good for longer, also driving style, like engine braking...

Gofastripes is right. My SMax went through rear pads and disks quicker than fronts. the fronts were massive vented disks, the rears were not vented and obviously much smaller but clearly the relative sizing of the systems meant they were not loaded up relative to the duty they were put under. But the rears were much cheaper.

Modern cars eat through disks much quicker...in the good old days of asbestos pads you got through two or three sets of pads for each disk, but now with modern metallic sintered pads the wear rate of pad vs. disk is much more even so not is basically 1:1. Also disks are not cast iron, they're cast steel.

"engine braking"

Are you from the 1950"s? no need for engine braking now. Engine is for making you go, brakes for making you stop. Engine braking  was from the days that pre-dated power assisted brakes where you were more concerned with preserving your braking leg, also when brake fluid was crap so brake fade was a consideration...no need to worry about brake fade with modern day brakes. Cars are so over-braked compared to the 1950's. Also they had cross-ply tyres which squirmed under heavy braking so engine braking prevented that, but with modern tyres they're easily capable of taking the loads modern cars and brakes can throw at them without getting all out of shape and un-supportive. With modern day brakes there is no need for engine braking. Brakes are cheaper than engines so why push more duty onto your engine instead of your brakes?

With a high revving petrol engine and driving on large roads with big intersections I find myself engine braking sometimes, mostly as a way of being in the right gear to accelerate again 🙂

Evening all,

Thanks for all the thoughts. I have now been able to inspect the discs and I am not surprised that one of them failed, the ribs connecting the two braking services are really badly corroded.

The front RH disc failed and similar cracks are visible on the front LH disc.

While I can sort of understand the corrosion my main concern remains that the van was serviced and MOT'd in June and handed back to me with no comments or advisories. I even paid for a brake clean in addition to the service....

I will be contacting Ford directly to discuss further now that I understand the failure mode.

Drive safe out there guys and girls!

https://www.flickr.com/photos/164739786@N06/31163237278/in/dateposted-public/

https://www.flickr.com/photos/164739786@N06/43224897490/in/dateposted-public/

Nasty, though I'm not sure how this would be spotted on an MOT unless there were visible signs of the cracking on the outside of the disk....they're not going to crack test the brake discs.

Also what's I involved in a brake clean and why would you think it was necessary? I've never heard of such a thing. Is it something you have had done before or regularly? i.e. a potential cause of the corrosion?

Good luck with Ford, though I don't hold out much hope of them taking any interest...they'll blame it on the brake disk manufacturer. I got no truck with them when the sidewall of my tyre split on a brand new car less than 6 months old where it was obviously not cut with a knife or done maliciously.

I even paid for a brake clean in addition to the service….

I'd be asking what was sprayed into the brakes.

I'm assuming a "brake clean" was just getting the pistons moving properly if a caliper was sticky

Hmmm, that can't have corroded all the way through each fin simultaneously? Do you have a new disk to compare it to, do all the fins connect the two sides together ? Just trying to figure it out, but it looks like the two sides of the disk must have been detached for some time otherwise there'd be a clean-ish surface where the two halves separated?

And +1 for what's a brake clean when you're paying for it?

Isn’t a brake clean a squirt of WD40 on the rubber gators holding the pistons in? Just so they don’t squeak?

TBH the rear discs on my roadster look a bit rusty too, I have been thinking about replacing all discs and pads.. Myself 🤣💪

BH the rear discs on my roadster look a bit rusty too, I have been thinking about replacing all discs and pads.. Myself

There's actually the same number of bolts on my Focus than there is on a mountain bike.

Bike:

Axle

6x rotor

Car:

5x wheel

2x calliper

How much of a faff the job is depend whether the disk sit in front of or behind the hub (or I think on some french cars the disk and hub are one unit!).

Yeah mine sit on the outside (I’ve changed the pads before) just wondering how much “haaarumph” I’m going to need to get the bolts undone 🤷‍♂️

Also, got to swing the callipers out of the way too .. but I’ve done that recently when I cleaned the surface and rubbers and pistons before putting the pads in.

That was easy.

I can’t ever remember a disc splitting in all the time I’ve been driving, and looking on the surface the OPs discs do look rather rusty for a recent aged vehicle.

Sure your van age is correct 🤣??

Its only the wheel nuts (and a tiny set screw) that hold the disk on to the hub with most fords (and many other cars as well) so if you've managed to get the wheel off you are 90% of the way there.

Are you from the 1950″s? no need for engine braking now. Engine is for making you go, brakes for making you stop. Engine braking was from the days that pre-dated power assisted brakes where you were more concerned with preserving your braking leg, also when brake fluid was crap so brake fade was a consideration…no need to worry about brake fade with modern day brakes. Cars are so over-braked compared to the 1950’s. Also they had cross-ply tyres which squirmed under heavy braking so engine braking prevented that, but with modern tyres they’re easily capable of taking the loads modern cars and brakes can throw at them without getting all out of shape and un-supportive. With modern day brakes there is no need for engine braking. Brakes are cheaper than engines so why push more duty onto your engine instead of your brakes?

Thats a great technique for burning through fuel, engine braking means more economy. Not sure how you figure it's going to wear though, it's getting the same lubrication regardless. Driving instructors seem to disagree with you as well.

Its only the wheel nuts (and a tiny set screw) that hold the disk on to the hub with most fords (and many other cars as well) so if you’ve managed to get the wheel off you are 90% of the way there.

Yeah... Then you've got to get the bloody things off because the last person didn't understand what torque settings are for, reset the calipers (provided they're not seized), potentially replace a nipple (because that was rounded), adjust the handbrake (my Mondeo helpfully has the adjuster under the heat shield above the exhaust centre section tunnel) and finally bleed the damn things (because yes, one was seized and needed replaced).

Don't get me wrong, it's not a difficult job but it's a pain in the arse to get done if things start holding it up, took me the better part of 2 days arsing about to get it done but was my first time doing a change since I was helped about 8 years ago. A pad change turned into pads and discs and then a nipple and then a whole new caliper. So about £190 all in for the actual bits. Then a rewind tool (possible to do without), hose clamp, disc cleaner (for the factory oil finish), high temp grease for the pins (for the love of god don't use copperslip! The Pagid stuff is good) and fluid. So that was another £65ish. Oh, and you'll want a torque wrench, properly torqued bolts make a world of difference when you come to take them off.

I never bothered with the set screw. To be fair the person that last replaced them clearly never either. They're just useful for holding the disc when building up, it does nothing otherwise.

Screws? You mean those countersunk screws are all that hold discs to the hub? 😳

I did wonder what they were when I took the wheels off.. so that’s made the whole process even easier then.

Mind.. £240 for a set of front discs and £90 for the rears 🤣 Quite why the difference when the rears are the vented types like the fronts, only smaller..

Awesome, thanks for that nugget on info chaps 👍

for the love of god don’t use copperslip! The Pagid stuff is good

It might not be copperslip, but EBC disk/pad kits come with a sachet of what looks like copperlsip.

But some people then say copperslip doesn't work with ABS (but have no justification for that). And the ceratec grease should be used instead.

In the end I gave up, the sliders still had some grease on them and the pistons moved freely so I didn't add anything.

Torque settings:

Wheelnuts "1 grunt" tight with a socket wrench

Caliper bolts same with a 7mm allen key.