I bought the car new 2017. Took it in today for normal maintenance. 65,500 miles (105,455 kilometers)

Of course I was expecting this but here's what surprised me.
The front brakes had 50%. The rears had 20% and that's what they wanted to replace. They also wanted to replace the rotors stating the the rear rotors the CX5 are made extremely thin and need to be replaced each time the pads are replaced. I'm not feeling any vibration associated with warped rotors.

So here are my questions:
(1) Is it common for the rear brakes to wear out before the front ones on a CX5? (They said YES)
(2) Is it true that the rear rotors on the CX5 need to be replaced each time the pads are replaced, or are they attempting to take me to the cleaners?

 

Shouldn't be any need for rottors.

Do you have a electronic parking brake or conventional parking brake lever?

 

Electronic

 

Electronic

 

Your dealer is lying about the rotors, that's total BS. If it was me, I'd have a talk with the service manager. Ne nice but ask him to show you the numbers for the thickness of the rear rotors as compared to what he says that they should be. Since they are not being truthful about the rotors I would also suspect the numbers thay gave you for the front and rear pads. I'd ask to see the numbers for those measurements as well.

 

@ Pep - Here is the poop on your "rear disk plate's"

• Minimum rear disc plate thickness - 8.0 mm {0.31 in}
• Reference: Mazda CX-5 Service & Repair Manual - Rear Brake (Disc) Inspection - Disc Brakes

I replaced the pads on my wife's CX-5 last year and I noticed what I do on all new(er) cars and that is that the front pads outlast the rear by more than 30%. My VW-GTI is the same in this. The brake fluid portioning valve is ported this way so the car doesn't nose-dive on hard stops. The rear brakes get the majority of fluid pressure and those pads wear out first. THIS IS BY DESIGN. It's NOT a problem. They are telling you the truth here. The rotors should be fine however. A quick check with a caliper for the 8mm thickness will determine that. Your "stealership" is "turning on the milking machine" IMHO.

 

A few points:

• The front end on virtually all cars do the vast majority of braking, the CX-5 included. Simple fact of life. Even the rear weight biased Porsche 911 generates more braking forces on the front of their cars than their rears (the difference just isn't as great as other cars).
• If, as you say, the proportioning valve sends the majority of fluid pressure to the rear pads was true, then the rear wheels would lose adhesion with the road surface due to forward weight transfer caused by braking. When the rear wheels lose grip, a spin is typically the result. Don't believe me? Cool, try yanking your parking brake on a snowy road sometime and see what happens.
• The reason why rear brakes wear out quicker is simply because they are much smaller than the front brakes.

 

Shipo … you are correct. It has much to do with the particular weight distribution of the car. Since most vehicles have engines in the front, a greater percentage of weight is forward vs in the rear of the vehicle, and brakes follow suit. Society is moving towards smaller and more practical cars. The CX-5 is very much a “stubby” car, and the front end is long. I’m about to replace both front and rear brakes on my 2019 CX-5 Signature, ordered the Cryogenically treated and slotted rotors and Carbon Fiber Ceramic brake pads. I was really surprised at how small the rear brake pads really were. The rear rotors are beefy, though, lots of thickness, just that the “pad” area is relatively thin, typical of rear rotors. And, btw, I’m also surprised at how large and beefy the front rotors are. I’ve owned Japanese cars for decades and these are surely the largest discs I have ever seen on a Japanese import. Again, points to weight distribution.