I loved this car but after 18 months the brake pads went bad. According to the dealer there was no reason and since the warranty on those expires at 12,000 miles or 12 months we were stuck with having to pay for all new rear brake pads and rotors. There is no reason they should have failed and Mazda Customer Service said "Too bad not under warranty". The MPG has also steadily declined after 6 months even with regular maintenance. I am disappointed since we bought it for it's supposed fuel efficiency and safety. After this experience I do not expect this to be a reliable long lived car and will not buy a Mazda in the future.
I'm no mechanic, but if your rear brakes were sticking (bad calipers, corroded sliders, etc.), then I would expect the rear pads to wear out faster than normal.
I'd also think that would affect your gas mileage if the brakes were constantly on.
I wonder if possibly your parking break was not fully released (I'm assuming that the parking brake is disc and not an internal drum type).
I also wonder if there is some item that controls the front/rear bias of the brakes that might be out of spec.
Lastly, I've read that the Honda CR-V goes through 2 or 3 sets of rear pads for every set of fronts.
Honda supposedly says this is "normal" for the CR-V.
Maybe the CX-5 is similar in this way.
I'd love to know if after replacing the brakes how your gas mileage responded if any, and what mpg you started with and what you got after that 6 month period.
I never heard of rear brakes going so soon. They usually last through two or three front brakes.
If this is a problem with Mazda... then they are not designing the brake system well.
Do a search on premature rear brake failure CX5. On repairpal dot com, it's a problem.
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