Brake Job @ 23K Miles ?!?

Looked at some of your photos in those threads.

The edge of the rotor surface not wearing; like the pad is too small to completely cover it. I had that happen on the HHR. Dealer wanted to turn or replace the rotors. I cleaned and greased the caliper pins, and put on new pads. After some miles, the unworn edge was down to shiny rotor surface.

The rotor surface flaking off, as on the rear side. That should not be happening, and I'd suspect defective rotors. Specially if this is what @Old Bear and others have seen with their brakes.

Japan does not use road salt in winters. It is one of the resources they are poor in, thus too expensive to just throw on the ground. This means their car companies had no experience designing cars and parts that would be exposed to road salt. The bed of the first Hilux/Tacoma that Toyota brought over would rust out, because the construction method used allowed salt to get trapped in seams. They should have the experience with salt for this to no longer be an issue, but it seems they forget. There is a thread about the metal backing to the Prime's hatch handle rusting. Just surface rust, but it shouldn't happen if a proper primer and coating for the environment was used.

 

I saw the post about the rusting hatch handle, checked my Prime and noticed the rust on it also. I haven't bothered to check it again since, and I'm not that worried about it. (much like the issue about the steering wheel cover leather/permatex flaking off in spots) I have and have had rust on every car I've ever had. Pics are nice to help with any explanation, but are no substitute for hands on evaluation.
And like nearly everything else someone else tests/evaluates for us, ask 10 people for/to evaluate an issue and be prepared for 10 different conclusions.

I have to agree that it is as possible that the dealers diagnosis of Old Bears Prime could be just as legit as the salt/rust premature brake wear explanation. There are plenty of variables in individual use case where just one different variable could make a situation defined as inside or outside normal. And on and on it goes, ie: normal, etc ...

 

OP long gone? A few pics would have been nice. I suspect the dealership wasn't completely off the mark, but who knows.

 

I just had my front brakes done @ 115,000 miles by my Toyota dealer. The pads were down to 3mm or less and the rotors were so badly rusted they were not turnable (we use tons of salt in Michigan). They also bled the brake lines. I know I paid more than at an independent shop but I know it was done correctly with Toyota parts and in a timely manner, so I'm happy.

 

Yeah I check our pad thickness every 3~4 years. At nearly 90k kms (~55k miles) they’re around 5 mm remaining. I think it depends a lot on driving conditions, location, where the car’s parked (garage vs street) and on and on.

I’ve been bleeding/replacing a quart of brake fluid every 3 years too.

 

That is a rusted & rotted brake rotor.

Find an independent shop that will examine the brakes while you watch, give you an explanation, and let you take photos. Send us the explanation and photos, and the thickness of the remaining pad friction material in millimeters or 16ths of an inch, not a guess at a percentage. Brake rotors are made of cast iron. It's great for thermal stability. Cast iron also rusts much more slowly than steel. As said above, some surface color rust is expected. It wears off easily.

Keep in mind how service departments compensate their people. The service techs get paid by the job. No job, no pay. The service writers get paid on commission. The more service work they sell, the more pay they take home. If they don't sell enough service work they get fired. It's a rotten system.

 

Only ONCE, in maybe 40 years of cars, we needed a rotor replaced. I think in that case it was due to pads dragging, they were wearing out fast, every 30~40k kms. And vehicle was past 150k kms.

Rotor cracked lol.

 

Tell them when I have braking issues I'll come back to you. Until then, I think i'll just keep driving it for a while.

BTW, this would be a good time to clean the brake rotors via a healthy longish slowdown from say 70-80mph down to 10-20mph 4 times then drive around a little just to cool them off again. You can also do 40mph to zero 8 times, just make sure you are actually using the brakes. Do it again just before your next visit to the dealer and see what they say about the brakes then.

 

Are you saying you wouldn't ever own a racecar or offroad only vehicle? Because brakes in those just don't last very long when you are flogging it at the track. Lol. Sorry I just couldn't resist.

 

Racecar?
No. I had an uncle that did that.
I can think of better things to waste my time and money on.

Track ONLY and off-road ONLY vehicles have to be trailered places....and the vehicle that gets them there needs to have more dependable brakes than a system that eats rotors every 25000 miles.

Real-World mileage WILL vary....

 

There are plenty of systems that won't make it 25k. mountain bike is one scenario even. But yes in general most cars should get longer. I have a mazda that had the pads in the rear fail after 27k. But that was mainly due to a defect in the caliper causing it to stick. Each set after that made it 70-90k. oddly enough the front set is still good after 250k lol.

 

And unless your Mazda had E-iLoop, it didn't have the benefit of regenerative braking to extend brake life further.

The only rotors I've had to replace before the car went 100k miles were on the Ranger. They warped, and I suspect that happened because the slide pins got sticky from disuse.

 

Actually it does have I-eloop. Japanese cars though tend to brake from the rear first. Though, I liken most of the braking usage probably comes from the radar cruise control on my mazda and adaptive cruise on my work prius prime. I do over 40k a year and it's practically a requirement for me to have the adaptive cruise option. Though, I noticed that in the rain especially heavy rain the mist off behind vehicles seem to blind the prime where the mazda at least in 2014 will see just fine.

 

Millimeter band radar like the Prime has can have trouble with fine water droplets. Any idea what the Mazda used for its sensor?

 

I know this thread has progressed well beyond the top of this page, but if I can back us up to
Brake Job @ 23K Miles ?!? | Page 2 | PriusChat
specifically the beginning of the 3rd paragraph
"The rotor surface flaking off, as on the rear side. That should not be happening, and I'd suspect defective rotors."
I tried to hint that it's hard to tell from pics exactly what one is looking at.

That area, is not rotor flaking off. That is pad material stuck on the inside of the rotor. I'd never seen that before, where pad material actually stuck to the rotors, like the one pad had been soaked in ? ? ? , had broken down and than adhered to the rotor. I looked at my pics again after I'd responded
Brake Job @ 23K Miles ?!? | Page 2 | PriusChat
and realized how easily one might think that one area on the inside of the rotor was rotor material flaking off. but it was actually pad material building up on the rotor surface. and the pad was worn down to a silly mm of so. I have more pics and still have the old parts too. I was going to possibly grind them smooth than take them in and have them turned. Probably not though, now.....

 

Whether rotor or the pad, that wasn't normal wear, and should have been covered by a warranty.

 

I wound't go into the many reasons past and present, why I didn't bother even asking for dealer service of those brakes. Neither of us in this household have ever been lucky with automotive service.