Glazed Front Brake Rotors

[Panther]

Hi All,

I have a 2016 CX5-GT AWD (32,000 miles) and on a 10 day trip to the Texas Coast ( Yes we have one ;-) ) when we returned home my brakes started kind pulsing when I come to a stop. I tried to clean them with some hard stops, but nothing seemed to help. I finally took it to my Mechanic and said that the Front Rotor's were Glazed, he'd not seen that look before, and the Pads (original) still had a lot of meat left on them and were clean, nothing embedded in them. Anyway he resurfaced the Front Rotor's and put new pads on, hes said the back ones were still thick and no need.
After he resurfaced it they were back to normal.

My questions is, would or does salt spray from the Coastal Waters and Winds cause a build up on the rotors? We're going back down there soon and I was wondering if trying to keep them washed off might help prevent this from happening again. I just don't want to be replacing rotor's anytime soon.

Appreciate any thoughts or ideas? Take Care. Be Safe.

Craig

 

[yrwei52]

Hi Craig, looks like you’re enjoying your retirement life pretty good!

The problem you have had certainly is a weird one. Did you actually drive your CX-5 into the sea water with hot rotors? Even that, I really don’t think that would cause warped or glazed rotors, and only at front? If you want to clean the rotors which may have salt, make sure the rotors are cool and hose them with water. Some say once the rotor is warped, it’ll do it again even if you turned it. If it happens again, just get a pair of new rotors.

 

[Panther]

Hi Ray !!!

Yes, I was made for Retirement !!!

Well, on the brakes, no never have driven it into the saltwater. I kept wondering if it just sitting
out in the parking lot with the wind off of the water would salt up the rotor and make it where they'd glaze or crust up ? The Mechanic who's really good said he's never seen anything like it, and that it was like a coating almost was applied to it ? I figured there might be some of the "Northern Boy's" that would know if salt would do that since they have to mess with the White Stuff, down here in Texas we all just stay home if we see that stuff since "No One" here can drive on it. ;-)

He said he just took a minimum off and that they weren't warped but just cleaned them up.

Thanks and Take Care,

CK

 

[Mete]

I have 2019 CX5 non-turbo. I have 93k mix of city and highway miles and I am still on the original brake pads that came with the car as new. I am surprised that they lasted this long. The brake just started pulsating when braking at high speed on a highway. From what I read, the factory pads are ceramic type. Today, I looked at the brake rotors and they are indeed glazed, apparently from brake pad material being deposited on the rotors. I live in Texas, but not close enough to the coast to get salt water or mist on the brakes. From what I read, sanding the rotor with #120 grit sandpaper followed by a rinse using a brake cleaner should remove the glazing. I am hoping that will resolve the pulsing brake issue. If that doesn't solve the problem, I will replace the rotors and pads. Since I am happy with the performance and longevity the original Mazda brake parts, I will stick with OEM parts. I have found two rotors and a set of front pads for $267 (including shipping) from parts.rentonmazda.com.
It does not make sense using after-market parts just to save something less than $100 when OEM parts last almost 100k miles.

 

[yrwei52]

I have 2019 CX5 non-turbo. I have 93k mix of city and highway miles and I am still on the original brake pads that came with the car as new. I am surprised that they lasted this long. The brake just started pulsating when braking at high speed on a highway. From what I read, the factory pads are ceramic type. Today, I looked at the brake rotors and they are indeed glazed, apparently from brake pad material being deposited on the rotors. I live in Texas, but not close enough to the coast to get salt water or mist on the brakes. From what I read, sanding the rotor with #120 grit sandpaper followed by a rinse using a brake cleaner should remove the glazing. I am hoping that will resolve the pulsing brake issue. If that doesn't solve the problem, I will replace the rotors and pads. Since I am happy with the performance and longevity the original Mazda brake parts, I will stick with OEM parts. I have found two rotors and a set of front pads for $267 (including shipping) from parts.rentonmazda.com.
It does not make sense using after-market parts just to save something less than $100 when OEM parts last almost 100k miles.

Yes 93K miles from factory brake pads front and rear is pretty good and you must have a lot of highway miles? Usually rear brakes are going at about 60K miles on CX-5.

You can turn your disk rotors to save some money ($25 ~ $30 each @ O'Reilly) with some inconvenience when you DIY installing the new pads. And make sure you know the “Maintenance Mode” for rear brakes with EPB and don’t turn the caliper piston while pressing in, or mention them if you have someone else doing it. Lubricating caliper pins with rubber friendly brake grease is the must. Changing the brake fluid is a good idea too.

I’m not sure if the factory pads are ceramic. And if you go for OEM brakes, make sure don’t get OEM “Value” brake pads and/or rotors. They’re cheap but are having too many complaints. If you see “MV” at the end of part number, skip it.

 

[Mazdiod2]

From what I read, sanding the rotor with #120 grit sandpaper followed by a rinse using a brake cleaner should remove the glazing. I am hoping that will resolve the pulsing brake issue.

I'm not sure exactly what type of abrasive is best but I have heard this type of service can help quite a bit if the rotors are glazed but not warped. I would probably give it a try before proceeding with new rotors.
I have heard a really hard stop can leave deposits on the rotors that are hard to remove because the heat bakes the material onto the rotor.

 

[Lazy2.5]

why were the pads replaced

 

[yrwei52]

why were the pads replaced

The common practice from a brake shop for the brake job is to replace the pads and turn the rotors at the same time just to avoid any unknowns. And this happened almost 4 years ago, the aftermarket brake pads could be as low as $10 with “life-time” warranty at the time!

 

[Lazy2.5]

The common practice from a brake shop for the brake job is to replace the pads and turn the rotors at the same time just to avoid any unknowns. And this happened almost 4 years ago, the aftermarket brake pads could be as low as $10 with “life-time” warranty at the time!

When the rotors are resurfaced, new pads bed in more easily to the new finish on the rotors? Why not just resurface the existing pads as well?

My "old" brakes had significant glazing on both the pads and rotors. It's from a combination of whatever gets onto them, as well as the heat. Apparently sticking caliper sliding pins can cause this.

 

[yrwei52]

When the rotors are resurfaced, new pads bed in more easily to the new finish on the rotors? Why not just resurface the existing pads as well?

My "old" brakes had significant glazing on both the pads and rotors. It's from a combination of whatever gets onto them, as well as the heat. Apparently sticking caliper sliding pins can cause this.

Well, new after-market pads is (was) cheap, why did the shop want to “re-surface” the pads? I’d believe new pads and “re-surfaced” pads will need about the same amount of time for bedding with re-surfaced rotor. But new pads sounded much better and cheaper.

 

[Lazy2.5]

Well, new after-market pads is (was) cheap, why did the shop want to “re-surface” the pads? I’d believe new pads and “re-surfaced” pads will need about the same amount of time for bedding with re-surfaced rotor. But new pads sounded much better and cheaper.

not resurfacing the pads, but rather sanding them down with sandpaper/ a wire brush and giving them a good clean.

If there is enough life left in them, you could do that instead of purchasing new ones.

 

[skid00skid0]

When's the last time you changed brake fluid?

I had a problem where the water in the lines rusted the slave cylinder pistons, locking the pads to the disk. I had to replace the calipers.

 

[Mete]

Good point. Thank for your advice.