Rear brakes gone at 15k..

bALLISTIC

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Mazda 2013 cx-5 touring (lemon)
Just got my 13 CX-5 back from the dealer after they had to install new pads and rotors due to winter road salt corroding my pads down to nothing..this is at 15000miles

Didnt get much warning, just metal on metal grind so the pads disengrated very quickly. I have the touring model and only the rear discs where affected but both of them where completely shot.

So a warning, if you hear the slightest squeak from the rear brakes don't hesitate to take the vehicle in, there is a service bulletin so at least Mazda has acknowledged the problem...
 
Paper work says TSB 04-003/14, thats all Im getting from it.

The dealer was informed of the SB only after calling Mazda..they were stumped as to why this would happen at only 15k and asked me questions such as, "Do you drive with two feet?" "Do you use the parking brake often?".
 
I would say replacing the rear brake pads and rotors at 15k way too soon. It is the front disc brake pads that usually wear out before the rear. It's good you caught it in time.
 
Had to replace my rear brake pads and disks at 48,000 miles (UK) but that was only because of a pad failure (friction material sheared off leading to metal-on-metal action). Have done plenty of driving on gritted winter roads (2 whole winters). The front pads and disks were checked at it's last service (50,000 miles) and had plenty of life left in them and the fronts do most of the work!
 
As I understand some Electronic Brake Force Distribution Systems will actually use the rear brakes more than the front ones under light and moderate braking.
The systems use the ABS system to monitor the wheel slip and redistribute the braking force as needed.
I guess this is done to reduce brake dive and reduce weight distribution under braking? the CX-5 actually has larger rotors in the rear than the front... (maybe for towing?)

This would all be fine if the rear brake pads were designed to deal with this increased use, but on some cars (honda and acura.. see below) the system seems to be added after the pads/rotors have already been selected.

A couple years ago Honda/Acura settled a class action lawsuit because the rear brakes wore out at 15,000 - 20,000 miles on the Accord and TSX. My dads' gently used 2009 TSX went through it's rear pads at 25k while the fronts were barely worn at all. I hope the CX-5 doesn't have similar issues!

From wikipedia:
"The pressure of the rear wheels is approximated to the ideal brake force distribution in a partial braking operation. To do so, the conventional brake design is modified in the direction of rear axle overbraking, and the components of the ABS are used."

Service manual infor about EBD on the CX-5 (It looks like under most braking conditions the rear wheels spin slower than the front!)
http://am.mazdaserviceinfo.com/emaz...3/CX5/mv/books/mvw04/html/id041500103400.html
 
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Mazda also applies more pressure to rear pads in light braking as it provides more directional stability especially when turning.
 
piotrek91 and GAXIBM - Yes, current gen C-class Mercedes do the same resulting in significantly higher wear on rear pads.

Of course, OP's rear pad (and rotor) wear was a problem as noted.
 
I noticed this thread back when it started and agree that 15k is way too soon. I have 53,000 miles on my CX-5 and the rear pads are gone. Rear rotors have some scoring in them. Fronts have decent life left as do drive mostly highway and what I consider normal wear. I tend to drive spiritedly and since I have a manual tend to downshift as needed and don't ride the brake. Anybody have ideas on how to get more even wear between the front and back. Being electronic controlled system, is it a software tweak? Right now I'll take suggestions on a quality long wear set of pads.
 
I noticed this thread back when it started and agree that 15k is way too soon. I have 53,000 miles on my CX-5 and the rear pads are gone. Rear rotors have some scoring in them. Fronts have decent life left as do drive mostly highway and what I consider normal wear. I tend to drive spiritedly and since I have a manual tend to downshift as needed and don't ride the brake. Anybody have ideas on how to get more even wear between the front and back. Being electronic controlled system, is it a software tweak? Right now I'll take suggestions on a quality long wear set of pads.
I think there's a pattern emerging here in which CX-5s have some kind of a rearward bias in terms of brake wear. Unusual for a predominantly FWD vehicle. I will have to keep an extra sharp eye on this. As for replacement pads, Mazda historically uses pretty well chosen pad materials on their cars (eg: Miata owners quite often replace with OE pads, even though they are pretty pricey). I would not jump to the conclusion that you will necessarily do any better going aftermarket.
 
My wife's rear pads on her 2001 Jetta used to wear out before the fronts too. I went through my entire CX5 brake system removing each caliper and rotor. With just 24,500 miles and 9 months old I was astonished to see the amount of corrosion on the rotors and calipers. The copious amounts of road salt the DPW uses around here I'm sure is to blame.
 
My wife's rear pads on her 2001 Jetta used to wear out before the fronts too. I went through my entire CX5 brake system removing each caliper and rotor. With just 24,500 miles and 9 months old I was astonished to see the amount of corrosion on the rotors and calipers. The copious amounts of road salt the DPW uses around here I'm sure is to blame.
Being a Californian, my reaction is always the same when I hear these kinds of stories. That's criminal! You'd think that by now states would have come up with an alternative to salt. If we can send a man to the moon (35 years ago!)...
 
Ah yeah, the moon argument, never gets old ;)! In truth, just about any substance that can dissolve in water will lower its freezing temperature, effectively melting the snow or ice. You cloud put sugar on the roads and it would work just fine. Parts of Canada have even been experimenting with beet juice. Airports use urea cristals (what makes urine yellow if you are wondering). The truth is that salt is the most commonly available and least expensive material to do the job. Oceans (and ancient sea beds) are full of it, there for the taking, no growing, basic production. Even with the cost of damage to our infrastructures and cars, salt is still the most economically sound alternative. Sucks really...
 
My wife's rear pads on her 2001 Jetta used to wear out before the fronts too. I went through my entire CX5 brake system removing each caliper and rotor. With just 24,500 miles and 9 months old I was astonished to see the amount of corrosion on the rotors and calipers. The copious amounts of road salt the DPW uses around here I'm sure is to blame.

What % of pad do you estimate was left, Front & Back?
 
On newer cars, we have a "device" called brake force distribution(I had a VW Rabbit-same as the Jetta). The rear wear comes from this device forcing the rear brakes more, then the front, to avoid the heavy deep when braking.
On VW, there was a problem with wrongly adjusted emergency brake, causing premature wear.
These days, we have to get used to replace twice the rear brakes, before we replace the front ones.
 
My 2001 Protege 5 needed rear break jobs every 20 000 km while the front were normal. My mechanic said it was a bad adjustment. So this is not new with Mazda...
 
What % of pad do you estimate was left, Front & Back?
that was a long time ago but I think we did the rears at least twice to the one time for the fronts in the 100,000 miles we drove it.
 
When I painted my front calipers I removed the pins to separate the caliper from the bracket. I was astonished to see very little grease in the holes and on the calipers pins themselves(less than 1000 miles). I've inspected brakes on new cars before (pre 2010) and remember seeing more grease from other manufacturers. Is Mazda being stingy with their lube?? Do they have a bad brake system factory worker?! I'd suggest lubing all metal-to-metal contacts with Sylglide on all these brake systems and making sure the braking system has no unwanted stiction. That being said, newer cars these days DO have more rear brake bias than older cars due to TCS/ABS control systems. But 15,000 is way too premature to be considered normal.


Also, notice in this picture, Mazda made the pads wider than the brake rotor surface, which is becoming a trend with new cars. I believe it's engineered to "clean" rusty lips on the outside edges, which may help with NHV and appearance.
 
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My 2001 Protege 5 needed rear break jobs every 20 000 km while the front were normal. My mechanic said it was a bad adjustment. So this is not new with Mazda...

Yes, on those models the rear parking brake is tied into the caliper, with it's own adjustment. It wasn't a common set up, and improperly adjusted parking brakes meant they were always grabbing the rotor slightly. I wonder if the CX-5's rear brakes use the same system. I will investigate and report back when I paint the rear calipers.
 
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