I noticed that I had pretty worn brake pads when I was swapping my summers on, so I grabbed a set of OEM pads to replace them. It seemed pretty early to wear them out, my Rx-8 got to around 40-50k with a few autocrosses on it before I replaced them.
This is on a 2021 Mx-5 RF with 30k. This car is a year-round daily driver, it has never been on track, never been even autocrossed. I have a 94 for that..
Both of the inside front pads are significantly thinner than the outside. The OEM pads have a bit more than 9mm, the outside pads on both the left have about 5.2mm, but the insides have a smidge less than 2mm!
I'm used to a bit of difference in a single piston caliper, of course, but I've never had that much difference even on a track car!
Any idea what's going on?
Thanks!
All 4 of the pins/sliders are pretty tight in there. Once you loosen them up, they slide nicely, though.
The top ones have a fancy bushing which I imagine would help with exactly this issue...
Stuck slider pins is my guess.
wvumtnbkr said:
Stuck slider pins is my guess.
That's my inherent feeling, but I've never seen this on a completely OEM thing with only 30k. This is the first time the brake caliper has ever been off. Plus the fact that both are worn exactly the same amount.
I guess I'll grease the pins a bit more and keep an eye on them at the winter swap.
I've also seen that from the pads not "floating" in the caliper bracket. However, that has only been with parts store pads that needed ground a little on the ears.
Yeah, I've ran across that too... The pads seemed smooth in the brackets, as to be expected with the OEM setup...
I dunno, I guess I'm just searching to know whether this is a systematic problem with the these cars or whether mine is special?
repoman
New Reader
4/14/24 8:35 p.m.
Wife's 2021 CX-5 had this exact problem. We toasted the pads front and rear by 20k miles after two years. It's not driven hard obviously being a commuter crossover but they tried to say we must be crazy drivers when the problem was definitely stuck or poorly lubed slider pins from the factory.
repoman said:
Wife's 2021 CX-5 had this exact problem. We toasted the pads front and rear by 20k miles after two years. It's not driven hard obviously being a commuter crossover but they tried to say we must be crazy drivers when the problem was definitely stuck or poorly lubed slider pins from the factory.
That's reassuring that at least I'm not the only one :)
Did you servicing it solve the issue for you for the second set of pads?
Is it happening at both front corners or just one? I've seen this a lot with NA calipers... I just swapped the inner and outer pads halfway through their life.
ShinnyGroove (Forum Supporter) said:
Is it happening at both front corners or just one? I've seen this a lot with NA calipers... I just swapped the inner and outer pads halfway through their life.
Both left and right fronts. I'm going to keep an eye on it and see how they're wearing in 10k or so.
repoman
New Reader
4/21/24 3:46 p.m.
WonkoTheSane said:
repoman said:
Wife's 2021 CX-5 had this exact problem. We toasted the pads front and rear by 20k miles after two years. It's not driven hard obviously being a commuter crossover but they tried to say we must be crazy drivers when the problem was definitely stuck or poorly lubed slider pins from the factory.
That's reassuring that at least I'm not the only one :)
Did you servicing it solve the issue for you for the second set of pads?
Late response, but yes so far so good after replacing all the rotors and pads. The tech at Mazda must have lubed the pins properly and fixed the factory's error. By this mileage after buying the car new there was all kinds of suspicious vibrations under braking and it's still smooth 10k miles after the service.
wvumtnbkr said:
I've also seen that from the pads not "floating" in the caliper bracket. However, that has only been with parts store pads that needed ground a little on the ears.
Cleaning the rust from the carriers so the pads can move freely is an annual service here. I have not uncommonly seen pads so seized that the brake pedal was low and spongy. The pads were flexing and returning back.
Probably not a case in a vehicle that isn't driven in a salty environment, though.
