Mazda 6 Tourer - Mazda 6 - Brakes Issues

Honest John Back Room » Technical matters
What is life like with your car? Let us know and win £500 in John Lewis vouchers | No thanks
View Threaded
Thu 16 Nov 2017 13:20
Mazda 6 Tourer - Mazda 6 - Brakes Issues - Miztaziggy

Good afternoon all,

Just after some advice on where to take this.

I bought a Mazda 6 in June 16 from a Mazda dealer in MK. The car was a year old with 20k miles. It has the remaining 2 years of the warranty or up to 60k miles.

Shortly after buying I noticed a vibration and the brakes juddering. So at the next service I took it to Mazda Doncaster close to where I work. They ended up skimming the discs under warranty.

Well before the next service, it started to judder again when braking. So this time I took it into Mazda York close to where I live. They again found the brakes were out and skimmed the discs.

Shortly after, it started to judder again, gradually getting worse to the point the steering wheel was shaking quite violently. It went back to Mazda York and they said the discs were out again but this time not enough thickness on the discs to skim.

Between buying the car and this point, there was about 40k miles. I was coming up to 60k miles by now and had had the car just over a year (yes I do quite a lot of motorway mileage).

After much back and forth they came back to me to tell me Mazda wouldn't replace the discs but would fit them for free if I supplied them. I just wanted it sorting so I said OK. Genuine Mazda discs are around £180 each I think, whereas Brembo / Pagit / Mintex are less than half that for a pair and have many good reviews online.

I supplied a pair of Mintex discs and they got fitted to the car. The dealer said they checked the pins / slide on the caliper and no issues.

Less than 5000 miles later, the judder is back.

I took the car to a local garage and he checked and confirmed the discs are warped again. He thought that if the issue keeps recurring the hubs may be out of alignment, but can't check as he doesn't have the equipment or the specifications to measure against.

I contacted the Mazda dealer in York again and I get the impression they're now trying to blame this on the non-genuine discs. They said they suggest I get an independent inspection and if that finds a fault, they'd submit another request to Mazda, which might / might not be approved?

Still waiting for a response to my latest e-mail.

I seem to have had nothing but problems with the front brakes since buying the car. I feel as though Mazda should honour their warranty and at least check there's not an underlying cause for the discs warping multiple times in 40k miles, but what can I do?

The Mazda website / customer services just point me back to the dealer. Where can I take it from here?

Should I have to fork out for an indepentent inspection in the first place?

Edited by Miztaziggy on 16/11/2017 at 13:33

Reply | Report as offensive | Link
Thu 16 Nov 2017 15:41
Mazda 6 Tourer - Mazda 6 - Brakes Issues - RobJP

Unfortunately, you've broken what is called the 'chain of liability', leaving you with the fitter of parts blaming the supplier of those parts, and vice versa.

If you'd paid an extra £100 or so, then you'd have had no problems. Liability would be on the Mazda dealer for supplying and fitting the parts.

As far as I see it, your only option is to get an independent engineers report carried out. At your expense.

Reply | Report as offensive | Link
Thu 16 Nov 2017 16:26
Mazda 6 Tourer - Mazda 6 - Brakes Issues - Miztaziggy

OK thank you for your opinion.

Assuming I went ahead and paid for a report, and it found what I suspect in that there is an underlying fault...

Would it be normal for the dealer / Mazda to reimburse the cost of the inspection?

Or...would I have to submit a claim through the small claims court / go to the motor ombudsman?

Reply | Report as offensive | Link
Thu 16 Nov 2017 20:17
Mazda 6 Tourer - Mazda 6 - Brakes Issues - SLO76
Sticking brake callipers (usually tears) are a common issue on Mazda’s. I can’t think of anything else that’s likely to cause disc wear like this. If it was an ABS issue I’d imagine it would flag up a warning light.
Reply | Report as offensive | Link
Thu 16 Nov 2017 16:39
Mazda 6 Tourer - Mazda 6 - Brakes Issues - gordonbennet

A few thoughts off the top of me head.

1. No offence here but are you too heavy on the brakes, plus if driven hard some cars demolish discs, my Rover 827 which had been a police training school car must have had half a dozen sets of discs in their 100k miles and that consumption continued in my use.

we'll assume you are driving normally, the above was just a suggestion, but might be worth looking on Mazda forums to see if this is common.

2. Too little effort on the back brakes, how are they wearing, i would expect similar wear of the pads and discs to the rear if indeed the rears are discs.

3. Are the calipers sliders and pistons properly lubricated, all round not just the fronts. Many garages do not service brakes adequately IMHO, a quick peer and a blast with some brake cleaner is about it at many places, some makers do not have a full brake strip clean lube regime as part of regular servicing, some reputable makes too which has surprised a few of us here, with the wise heads paying a good indy to take on the work every other year.

If caliper pistons and sliders are not properly lubed then by years 3/4 things start to seize up, i'm guessing that the calipers are single piston type both ends with sliding pins to enable the equal distribution of pressure so the disc is 'clamped' centrally as it were, what happens when a pin sticks in place is the pad being pushed by the piston itself does inreasingly more of the braking with the disc being forced over time after time, plus that sticking pin is reluctant to extract following braking, leading to binding.

A similar thing can happen with twin piston calipers or even 4 piston calipers where the pistons are opposed, the caliper in this design is solid on its carrier and the pistons alone do the work, obviously they need to retract freely or you get overheating and odd wear.

If one or more pistons start to seize you can end up again with one pad receiving more brake pressure and again the disc is forced over.

If the rears are not fully free you can end up with the fronts doing more work than they should leading to overheated front brakes, indeed even changing the make of brake pad at one end can cause a slight imbalance of effort front/rear as different materials have different behaviours.

Before ABS you'd have an inkling something wasn't right because you would get premature lock up at one end (usually the front) on slippery surfaces, but with ABS you don't get that feel in quite the same way.

Sorry its been a lot of waffle to read, i'd be more inlinded to let a competent indy have a good look at the brakes, i suspect lack of full servicing in the brakes is at the root of this.

Oh and i too would be running Brembo discs and pads.

Edited by gordonbennet on 16/11/2017 at 16:43

Reply | Report as offensive | Link
Fri 17 Nov 2017 12:56
Mazda 6 Tourer - Mazda 6 - Brakes Issues - galileo

I think it has also been mentioned that holding on the footbrake at the foot of exit slips with traffic lights tends to cause warping if the discs are hot?

(Not suggesting the O/P does this, just adding it to Juddian's very comprehensive list of possible causes)

Edited by galileo on 17/11/2017 at 13:00

Reply | Report as offensive | Link
Fri 17 Nov 2017 13:58
Mazda 6 Tourer - Mazda 6 - Brakes Issues - Miztaziggy

Thank you for the replies.

In answer to those points:

When they changed the discs about 4k miles ago, they serviced the calipers, I believe they replaced the slide pins and lubricated them, to make sure this wasn't the issue.

The car kind of vibrates pretty much all the time, but quite badly between 70 and 85. It feels like the rear, and I assumed it was from a tyre that had a puncture repair done. I've since had 4 brand new tyres put on and the vibration is exactly the same. It can be felt sometimes in the steering wheel, especially if turning right at around 60/70mph and not braking.

I drive a lot of mileage for work and I drive my car quite steadily. I tend to do 70-75 and I brake quite gently. I'm very conscious that it's my car and it'll cost me a lot of money if I rag it around, in tyres, brakes, fuel etc etc.

I do consciously try not to hold it on the brakes at lights and things, but the car has auto hold when on hills so it's applying the brakes. It also has electronic handbrake, which I assume is applying all 4 brakes when used.

The independant garage that checked the brakes said he thought it would be the hubs out of alignment. I'm no expert so I'm not sure, but something is causing the brakes to keep warping and a constant wobble / vibration.

Reply | Report as offensive | Link
Fri 17 Nov 2017 23:33
Mazda 6 Tourer - Mazda 6 - Brakes Issues - focussed

If the OP is very gentle on the brakes there is a possibility that the discs are glazing.

The old-time fix for this was to fit a set of abrasive pads, I have no idea if they are still available though.

These pads had some sort of abrasive coating which scuffed the discs true and removed any glazing.

Years ago there was a widespread problem with brake discs in service due to the way they were manufactured - they were cast with a very small allowance for machining on the working faces, and when cast the surfaces would "chill" in the mould which hardened the surface, but the machining allowance was not enough to get rid of all the hard chiiled surface, so what you got was part of the disc soft and part was hard, contributing to uneven wear of the thickness of the disc which resulted in brake judder.

I wonder if that problem has re-appeared?

Reply | Report as offensive | Link
Sat 18 Nov 2017 10:20
Mazda 6 Tourer - Mazda 6 - Brakes Issues - bazza

You say the vibration is there when not braking. I'm wondering whether the discs are not the source of the vibration and it's actually something else. Not tyres as they've been replaced. I've not known warped discs for many years and then it was back on an Astra and noticeable only when braking, the vibration felt strongly through the steering wheel. Have a good mechanic check your driveshafts, inner and outer CV joints, it could be a problem here,although potentially costly to diagnose and fix. As a long shot, put your front wheels on the back, does it make a difference, just possible you've got a duff rim. Electronic handbrake works on the back in my experience by the way.

Reply | Report as offensive | Link
Tue 6 Feb 2018 21:36
Mazda 6 Tourer - Mazda 6 - Brakes Issues - rogerzilla1

How many miles did you cover before the problem came back? If it was up to about 3,000, the discs probably have runout due to a dirty mating surface with the hub (rust or grit). Many lazy mechanics fit new discs without cleaning the hub properly, so everything is fine for a while and then the vibration starts under braking. It's called disc thickness variation and is caused by the pads "kissing" the two high points of the misaligned disc and gradually thinning it there.

A competent mechanic will clean the hub face carefully with a rotary wire brush before fitting a new disc. It's not hard to do and I've fitted discs myself which have run for tens of thousands of miles without problems. A really, really good mechanic will also check runout with a dial gauge after fitting, but this is impractical where the disc is only held in place by the roadwheel.

Reply | Report as offensive | Link

10 warranty myths exposed

Here’s how to sort the fact from the fiction when it comes to car warranties.

Cheap Car Warranties