My rear brake fiasco (dealership, I know)

What a horrible experience!

The new wear doesn't look normal but it is too early to say definitively.

On my last brake job the wear looked sususpicious (I had a dark strip in the middle of the rotor).

After driving a few thousand km the wear is normal and uniform.
 
What a horrible experience!

The new wear doesn't look normal but it is too early to say definitively.

On my last brake job the wear looked sususpicious (I had a dark strip in the middle of the rotor).

After driving a few thousand km the wear is normal and uniform.
Trying to keep this mindset, and thinking they reused the burnt pad or there’s debris on the pad. Playing wait and see…I’ve admittedly done a ton of googling for validation and I’m seeing so many posts (including on this forum) with similar wear, and it turned out to be “normal”. But who knows.

This thread here https://bobistheoilguy.com/forums/threads/is-this-wear-on-new-rotors-and-pads-normal.294555/
 
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This rear rotor on my BMW looks better. You see orange color? That is bcs. it spent around 270mls on track, and I actually managed to put pads on fire.
The rotor was removed after 30,000 miles. During the life of that rotor, I switched between race pads (hard) on track and regular pads after track time. It was a Pagid rotor, and the cost was, I think, $34 per piece.

View attachment 197873

Yeah. Went on a walk earlier and naturally looked at every single rotor on the street and shook my head, since they all looked pristine.
 
Can't you at least shoot each side with an IR gun after driving? If the problematic side is consistently, noticeably warmer than the other that probably means something
 
If I were doing that job the first thing I would do is pressure test the caliper. You put the block in with no or one pad depending on the caliper, apply the brake and see how much pressure it is making. Have an assistant press the brake and watch the gauge to see if it returns to zero and how fast it returns, it should be almost instantaneous.
Apply and retract the park brake and watch what it does. I have had one for some years and it really proves its worth finding sticking calipers, bad lines and proportioning valves, MC, etc. A good made in the USA tool. The dealer or any mechanic worth is wrenches should be able to do this, if not find someone who can or buy the tool and DIY.


Tangentially related, I chatted with the guy at tooldiscounter at length awhile back. I think he was incredibly busy (based upon my wait time), but once I got to speak with him he was incredibly helpful and really friendly. Highly recommend these guys.
 
Can't you at least shoot each side with an IR gun after driving? If the problematic side is consistently, noticeably warmer than the other that probably means something
I gotta go to Home Depot tonight, so I’m actually gonna buy one. Good idea. Will report back

Came back to edit...this is actually a fantastic idea. It literally cannot be disputed if there's a temp difference. I touched em both last night and they both felt fine, but this will give some peace of mind....here's to more money spent on this ;-). $45 but still...
 
Maybe old, dried grease on caliper slide ?

I hate incompetence and having to pay big $$$ for it.

:mad::(🤬🫣
 
Maybe old, dried grease on caliper slide ?

I hate incompetence and having to pay big $$$ for it.

:mad::(🤬🫣
It feels like incompetence follows me everywhere I go, unfortunately. My fault for not following my gut from years of dealer experiences.
 
I gotta go to Home Depot tonight, so I’m actually gonna buy one. Good idea. Will report back

Came back to edit...this is actually a fantastic idea. It literally cannot be disputed if there's a temp difference. I touched em both last night and they both felt fine, but this will give some peace of mind....here's to more money spent on this ;-). $45 but still...
Harbor Freight or maybe even AutoZone might have less expensive offerings. Seems to me most IR guns are relatively accurate for general use

A laser dot can be nice but not mandatory. And if you can find capability greater than 500*F that's kinda nice, esp for exhaust stuff. But for your use up to 500 oughta be ok
 
Harbor Freight or maybe even AutoZone might have less expensive offerings. Seems to me most IR guns are relatively accurate for general use

A laser dot can be nice but not mandatory. And if you can find capability greater than 500*F that's kinda nice, esp for exhaust stuff. But for your use up to 500 oughta be ok
I'm getting a Klein tools one, seems to have the better reviews than whatever else Home Depot has. It reads up to 752*. Plus, can always use an extra outlet tester...Kind of excited to have this anyway because I always wondered how hot my mantel gets when I've got my fireplace going!

 
Alright! Jury is out…inconclusive, to my non-mechanical mind. You guys tell me. I took readings after a short drive to the grocery store, one that was almost identical to when my rotor was glowing red last time. Did some harder and longer braking just to get temps up. I took these readings right when I parked. Did it by the caliper and opposite the caliper since my assumption is it would be hotter near the pad. Video below.



Anyway, the groove mark on the problem rotor measured around 170F, going from 110 to 160ish across. The rotor on the other side appeared to max out in the 140s. So, to me, 30 degree variation is not incredibly noteworthy, at least to warrant major concern. Could this be more evidence pointing to a pad problem? Again, in my non mechanical opinion, I feel like if anything was seized or dragging like the parking break we’d be seeing much more significant temps like 100 degree difference, or…a glowing rotor.

Also want to state that this is the best my car has ever felt braking but I’m sure that has to do with the fact I literally have brand new pads and rotors on all wheel, which I’ve never timed like that except when I have bought a new car. No noises, no apparent pulling when braking, no smell. The only difference is the car feels tighter and I definitely have a light pull to the left.

Whatcha guys think? Thanks for entertaining my nonsense, I know this is kind of absurd.
 
Is the rotor still turning red when driven normally? I am a little confused. There is no binding in those brakes.
Dude, no way, thankfully. That hasn’t happened since last Friday pre-caliper and hose replacement.
 
Oh okay now I get it, sorry I misunderstood, I thought the rotor was turning red after it was repaired. Don't worry about it with those temps.
 
Oh okay now I get it, sorry I misunderstood, I thought the rotor was turning red after it was repaired. Don't worry about it with those temps.
So you think the “early onset grooving (light gouging) is from the pad? Obviously no way to say for sure without looking at it.
 
Good evening - it's been a while since I've posted on here. Good to be back, I guess! I just wanted to share my rear brake job fiasco, and maybe get some further insight from the pros here. Kind of long but want to give the whole bit of context.

So, I have a 2017 Mazda CX-5 sport, 71K. Bought it used in 2020; in that time I've replaced the front pads and rotors twice, and my rears made it to a whopping 3mm at 70K. I was pretty impressed, until they started making some serious grinding and squeaking noises from the driver side. Until recently, I've brought my car in for routine maintenance at a trusted independent shop, but it's far from my new house and his prices started to rise. I saw an oil change special for my local dealer where I bought the car (literally a 4 minute drive) that was competitive and thought "ah, what the hell!". Had great service. WiFI, coffee, nice...Such a great experience I even decided to get an overpriced front brake job done by them (November, 2023). No issues to speak of, and everything was dandy. About a month later, the rear grinding was unbearable. Decided to take it in. This is where everything went south.

They slapped new pads and rotors on and sent me on my way. I had thought it was a little odd that they didn't mention anything to me about the rotor with the grinding, that it had a noticeable gouge/score mark that the passenger side didn't. Maybe a faulty pad after 70,00 miles, what do I know. I noticed that the brakes smelled a little, but it wasn't too different than the "normal" material burning smell you get with new brakes. Until Friday, when I got out of the car and saw my entire rotor glowing bright red. They maybe had 25 miles on them at this point. Brought it back the next day; many-a-mechanic on Reddit told me it must be the caliper seized or a collapsed flex hose, so I mentioned that to them. They did in fact determine the caliper was seized; I had to insist on them replacing the hoses because "they weren't leaking, so they're fine" (knowing that they can fail inside out).

The dealer was kind enough to replace the rotor, pads, and caliper, and parking brake mother on that wheel at no charge, only I had to fork out the cash for a brake flush and new hoses (I did both sides to be safe). I felt that this was a good compromise, even though I was annoyed that maybe they should have investigated the issue prior to giving me new pads and rotors. When I picked my car up today, before I went in the shop I investigated the new parts...hoses, caliper, all clearly new. Except the rotor...looked a little grooved. All of the other brand new rotors on my car, you can still clearly see most of the cross hatching and there is no grooving. So it raised some alarm bells. I politely brought it up to them, until I wasn't so polite because I couldn't believe that a brand new rotor with only a mile or two on them could already have groove marks on them. So, they put another brand new rotor on in front of me (I hate being this kind of customer, seriously, but I felt it was warranted). Sure as hell, as soon as I get home, there's groove marks on it again. The brakes don't make any unusual sounds, don't smell, and don't appear to be hotter on touch than the other rear rotor. I do feel like the car pulls to the left at coasting a little bit; RPMs all seem to be normal, I rolled fine from drive into neutral, and it doesn't pull when I brake, so nothing seems out of the ordinary. Am I overthinking the almost immediate grooving on the rotor; is it possible they left the old burnt pad on (which they insist is new?). Little impatient at the whole situation, to be honest.

Thanks!

Photos in order;
1) New rotor groove
2) New caliper
3) New flex hose
4) Inferno
5) Rear driver rotor before replacement
6) New rotor groove (2)
7) Rear passenger nice and smooth
there should not be any grooves on the rotor especially if all parts have been replaced with new. I have power stop oe replacement rotors and pads which have 1,000 or so miles on them and haven’t noticed any abnormal wear gouging etc. ask the dealer if the guide pins were replaced.
 
there should not be any grooves on the rotor especially if all parts have been replaced with new. I have power stop oe replacement rotors and pads which have 1,000 or so miles on them and haven’t noticed any abnormal wear gouging etc. ask the dealer if the guide pins were replaced.
Agreed, which is why I think a) they never replaced the burnt up pad and/or b) something is still dragging (temps appear to disagree).
 
If you did the original work at another shop do you think they would investigate the source of the original uneven wear or just slap on new pads and rotors as well?

I honestly think most shops would go through the exact same repair process, but they wouldn't give you a caliper or change the rotor a second time.

Most places slap on new parts. If the problem is still there they will start diagnosing.

One of my family members had a problem with a brake job. When they took the car back, the mechanic said he doesn't know what happened, and asked for the full price to redo the brake job. :ROFLMAO:
 
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