Needs Brakes Already?!

Wildeyed

Wildeyed

Well-Known Member
I took my car in for the seasonal tire swap and requested annual brake maintenance (lube, clean, etc ) while the tires were off.
They didn't do the work because my rear brakes are worn down to 1mm and now rotors and pads require replacement.

I was not/am not happy. It seems to me that with only 47k on the odometer that kind of brake wear is nuts. On an EV it should be unheard of!

My Service Manager agreed that it's not normal but could offer no explanation. Has anyone else had similar premature wear? Am I correct that this is not what should be expected at 47k on an EV? Is there anything I should look for as a cause, any future proofing I can do to ensure this doesn't happen again...like, ever?! Thanks.
 
I suspect the cause is that rusty rotors wear pads quickly. So, it wasn't normal use of the brakes but that of the pads having to wipe off rust, which is quiet abrasive.

I noticed my left front disk was rusting along one edge of the contact area and wearing the pad unevenly. The more it wears the less effective that part of the pad is at cleaning off the rust so it just gets worse.

As a side note, the Ioniq 5 turns off blended regen for the first 10 or more brake cycles to help clean the pads, but only when in Level 0.
 
I hardly ever use my brakes in favour of the Regen paddles. Once or twice a month I shift the car into neutral while going downhill to gently scrub the brakes of rust.

I've owned many cars over the years and have never required brake parts replacement before 80,000 km...and on some of my cars, I never required any brake work.
 
If you have last years inspection it will show what the pads were then and you can compare. New pads are generally 10-12mm in thickness
Mine at 32,000kms (last Feb) were at 10/11mm, my annual is coming up again in Feb so I'll see what they are then.
47,000kms sound way to early even for Ontario, maybe the tech was reading cm instead of mm. I wonder if non-Hyundai parts would wear any better.
I don't use the paddles but I'm defaulted to lvl3 for regen and the brakes only get used coming to a full stop.
 
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EVatLast said:
If you have last years inspection it will show what the pads were then and you can compare. New pads are generally 10-12mm in thickness
Mine at 32,000kms (last Feb) were at 10/11mm, my annual is coming up again in Feb so I'll see what they are then.
32,000kms sound way to early even for Ontario, maybe the tech was reading cm instead of mm. I wonder if non-Hyundai parts would wear any better.
I don't use the paddles but I'm defaulted to lvl3 for regen and the brakes only get used coming to a full stop.
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They didn't report any specs last year, presumably because everything was fine. I was wondering whether parts other than OEM Hyundai parts might be a better choice but I don't have the first clue about judging such things. I know that it's going to cost between $600-700 to have the work done.
 
A decent set of rear pads and rotors will run from $200 to $400 just for the parts and maybe an hour for install. I wouldn't go cheap on the parts just because of the weight we're trying to stop.
Do you have a trusted mechanic/advisor go to for advice? Might even be worth trying an after market brake shop.
 
Wildeyed said:
I hardly ever use my brakes in favour of the Regen paddles. Once or twice a month I shift the car into neutral while going downhill to gently scrub the brakes of rust.
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You've actually answered your own question! Use the brake pedal more often. Once or twice a month is simply not going to do it.
 
KiwiME said:
You've actually answered your own question! Use the brake pedal more often. Once or twice a month is simply not going to do it.
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But if we're talking about excess wear how would using the brakes more cause less wear? Also, I'm using the car as it's designed to be used and the brakes are wearing early. That's what I see as the issue. Or, at least one of the issues. The other being that the OEM parts are maybe not so hot.
 
Wildeyed said:
But if we're talking about excess wear how would using the brakes more cause less wear?
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As explained, the rust is abrasive. Letting it build up for a month means when you "knock the rust off" you're hitting the pads with 60-grit sandpaper. If you did it more often, you'd be dealing with less rust buildup and thus less wear overall. Might be interesting to actually observe the roughness of the brake rotors after a month and see just how bad it gets.

It's also not entirely impossible that, since you use the brakes so infrequently, the calipers are starting to stick and the pads are rubbing even if only slightly. Did anyone happen to note if one pad was significantly more worn than the other? Do you use the parking brake regularly?
 
Genevamech said:
As explained, the rust is abrasive. Letting it build up for a month means when you "knock the rust off" you're hitting the pads with 60-grit sandpaper. If you did it more often, you'd be dealing with less rust buildup and thus less wear overall. Might be interesting to actually observe the roughness of the brake rotors after a month and see just how bad it gets.

It's also not entirely impossible that, since you use the brakes so infrequently, the calipers are starting to stick and the pads are rubbing even if only slightly. Did anyone happen to note if one pad was significantly more worn than the other? Do you use the parking brake regularly?
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I see your point now.

One of the reasons the service manager was puzzled about the cause of the early wear was because both sides were the same, one millimeter. There was no asymmetrical wear. (I've had a frozen caliper before so I've seen what that can do). Yes, I use the parking break all the time. Is that a good or bad thing?
 
Wildeyed said:
Yes, I use the parking break all the time. Is that a good or bad thing?
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IMO, a very good thing. Parking brakes often go unused so long they rust solid, then when you finally do go to use them they either won't engage properly or worse, engage and refuse to release... then you're dragging the brakes and wondering if that smell is you or the guy in front of you. :confused:
 
Genevamech said:
Parking brakes often go unused so long they rust solid
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Maybe killing 2 birds with one stone is not a bad thing.
Wildeyed said:
The other being that the OEM parts are maybe not so hot
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I checked my service records on my original Dec 2018 MY (same ~ manufacture date as your own) and the first year report showed 8mm pad remaining all around after just 7600 km.
Last month my replacement 2021 MY was in for brake service and indicates 10mm (front) and 9mm (back) after accumulating ~ 15,000 km (2nd year service).
I have reduced the default regen level to 1, on the original it was set to 3. I feel this helps even wear a little when braking, although with no regeneration application with the rear brakes, the wear will be slightly higher as expected.
Not sure if better quality pads or the regen adjustment has been the difference, but also by reducing the regen default level, less strain is applied to the drivetrain...hopefully avoiding the drivetrain issue occurred on my original model (so far so good).
I hope the repairs go well and reestablish the satisfying and secure feeling of brakes performing as they should, it really is a good system compared to other manufactures:)
 
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