Who else has had warped rotors?

[Phil11]

With the vibrations is this something you are feeling in the break peddle or steering wheel or seat or some combination? Want to be on the look out as I approach 9k miles.

Medium to hard breaking at about 70-100klm whole front of the car and steering wheel vibrates, sometimes worryingly so... doesn't feel too great.... lol

 

[Scott D.]

I leased the car in January of 2018, had my rotors replaced in Aug 2018. And one year later, I am having the same problem. So again, I will contact the dealer and make arrangements from my busy schedule to bring the car in. I love this car, it’s fun to drive and looks great. But this (for me) says quite a bit about Kia as a brand. They are not ready to compete with the big boys of the car world.

 

[NS_Stinger]

I thought after rebedding the brakes last week I had solved this issue but it's already back just as badly as before. It looks like it's mostly my drivers side rotor thats causing the issue, you can clearly see lines of pad deposits all over it. Now I have to decide whether to go have a dealer waste my time with a temp fix or go and buy/install new front pads and rotors...not cool KIA

 

[MerlintheMad]

I leased the car in January of 2018, had my rotors replaced in Aug 2018. And one year later, I am having the same problem. So again, I will contact the dealer and make arrangements from my busy schedule to bring the car in. I love this car, it’s fun to drive and looks great. But this (for me) says quite a bit about Kia as a brand. They are not ready to compete with the big boys of the car world.

You would feel that way, being one of the "afflicted". I, on the other hand, feel quite oppositely. My brakes at 22K+ miles are excellent, the best brakes I have ever used in fact. Most of the drivers on the forum would agree that the brakes on the Stinger are very, very good.

Above: "warped" rotors are not warped, they are different thicknesses because of pad deposits. I wonder if you've read through any of this? (and the other threads; there is copious discussion on pad deposits and what it takes temperature-wise to actually warp a rotor)

 

[itguy61]

I thought after rebedding the brakes last week I had solved this issue but it's already back just as badly as before. It looks like it's mostly my drivers side rotor thats causing the issue, you can clearly see lines of pad deposits all over it. Now I have to decide whether to go have a dealer waste my time with a temp fix or go and buy/install new front pads and rotors...not cool KIA

If Hilo's theory about cementite is correct that would explain why it comes back so fast after bedding again. Have to replace or get them cut to get that crap out of the rotor.

 

[ShannonC]

A interesting article which may change some thoughts and also reinforce others. It's a long read but worth it.
Myths of the Braking System

 

[Phil11]

You would feel that way, being one of the "afflicted". I, on the other hand, feel quite oppositely. My brakes at 22K+ miles are excellent, the best brakes I have ever used in fact. Most of the drivers on the forum would agree that the brakes on the Stinger are very, very good.

Above: "warped" rotors are not warped, they are different thicknesses because of pad deposits. I wonder if you've read through any of this? (and the other threads; there is copious discussion on pad deposits and what it takes temperature-wise to actually warp a rotor)

I don't claim to be an expert on cars by any means, but when a qualified Kia dealer mechanic tells you the discs are warped and they are replacing them for that very reason... I have no reason to doubt his qualifiaction

 

[MerlintheMad]

I don't claim to be an expert on cars by any means, but when a qualified Kia dealer mechanic tells you the discs are warped and they are replacing them for that very reason... I have no reason to doubt his qualifiaction

"Warped" is a term describing the effect of uneven rotor surfaces. I don't think it matters how that happens. An uneven surface is crap. And if the cementite theory holds, the damage has been done and is irreversible; and only new rotors will stop the vibrating.

 

[MisterMac]

@Phil11, warped is a generic, common term used to describe uneven rotors. Do not confuse it with the same term energy applied to wood, for instance.

 

[Manaz]

I don't claim to be an expert on cars by any means, but when a qualified Kia dealer mechanic tells you the discs are warped and they are replacing them for that very reason... I have no reason to doubt his qualifiaction

"qualified Kia dealer mechanic" or Carroll Smith, with more than 40 years of professional racing, including the Shelby/Ford GT 40s – one of the most intense brake development program in history, who says "I have never seen a warped brake disc". The Myth of Warped Brake Disks - Interesting Read from Stoptech

I know whose word I'd take.

 

[ShannonC]

See post #446

 

[MerlintheMad]

A interesting article which may change some thoughts and also reinforce others. It's a long read but worth it.
Myths of the Braking System

"Depending upon the friction compound, easy use of the brakes for an extended period may lead to the removal of the transfer layer on the discs by the abrasive action of the pads. When we are going to exercise a car that has seen easy brake use for a while, a partial re-bedding process will prevent uneven pick up."

So if you're like me, and your brakes were broken in slowly and easily, before tracking the car, do the vigorous bed in process: analogous to stretching and doing light exercises before engaging in some serious athletic demands of the body. If you just take the Stinger out there and start heavy braking before each turn, you're going to get lumpy brakes (or at least the risk is great).

"The only fix for extensive uneven deposits involves dismounting the discs and having them Blanchard ground - not expensive, but inconvenient at best. A newly ground disc will require the same sort of bedding in process as a new disc. The trouble with this procedure is that if the grinding does not remove all of the cementite inclusions, as the disc wears the hard cementite will stand proud of the relatively soft disc and the thermal spiral starts over again. Unfortunately, the cementite is invisible to the naked eye.

"Taking time to properly bed your braking system pays big dividends but, as with most sins, a repeat of the behavior that caused the trouble will bring it right back."

Surely, this answers 99% of all complaints here. Surfacing rotors is done by "rote" , by those who don't have any scientific way of determining if the "Blanchard ground" has in fact removed all the cementite spots; and therefore the aggrieved spots remain: which of course results in a few weeks or months (at best) before the lumpy brakes return. Time to get new rotors and do the bed in. This article details how to go about that more fulsomely than anything I've read so far. I'm saving this page!

 

[itguy61]

Yeah, I am not sure how far it gets us though. I read further down in that forum and there were people that absolutely loved the stock pads and had no problems. I guess in the end, it could have something to do with pads, rotors, systems, and the driver in some odd combination. We may never find the actual circumstances that create this issue with the brake deposits... regretfully.

Help you may be on to something, a combination of the rotors and pads may be the culprit. The only problem is to prove it somebody has to be willing to run stock pads on their nice, new aftermarket rotors to see if it happens again. I would bet you are not going to see anyone try to verify that with the price of the aftermath rotors! I have about 4K miles on my Gyrodisc pads so only time will tell if I see the problem again. There again though I put new stock rotors on with the new pads. If I were doing it now I would order aftermarkets from Nick. D

Did you put the aftermarket pads on new rotors or reuse the old ones with a turning?

 

[MisterMac]

Help you may be on to something, a combination of the rotors and pads may be the culprit. The only problem is to prove it somebody has to be willing to run stock pads on their nice, new aftermarket rotors to see if it happens again. I would bet you are not going to see anyone try to verify that with the price of the aftermath rotors! I have about 4K miles on my Gyrodisc pads so only time will tell if I see the problem again. There again though I put new stock rotors on with the new pads. If I were doing it now I would order aftermarkets from Nick. D

Did you put the aftermarket pads on new rotors or reuse the old ones with a turning?

Actually, I ran close to five thousand miles with stock pads on my new rotors and I had zero problems. I only put on new pads because I wanted them.

 

[itguy61]

Actually, I ran close to five thousand miles with stock pads on my new rotors and I had zero problems. I only put on new pads because I wanted them.

I am running new stock rotors 4k miles ago. I did so because it had vibration when I got it and started again in about 1500 miles.

 

[MisterMac]

I am running new stock rotors 4k miles ago. I did so because it had vibration when I got it and started again in about 1500 miles.

When the dealership put my new rotors on, I had the service manager bed the brakes twice. Then I immediately did it myself. Maybe that prolonged the time before hot spotting?

 

[Helo58]

Did you put the aftermarket pads on new rotors or reuse the old ones with a turning?

I have experienced several "iterations" for various periods of time.
1) Stock rotors and stock pads for 7k miles.
2) Turned rotors and stock pads for 1k miles.
3) New OEM rotors and aftermarket pads for 2k miles.
4) Turned rotors and aftermarket pads for 2k miles (current configuration).

In normal city driving, to and from work, I thought the issue was getting (got) better. I just returned from a trip to the NC mountains and was going back and forth with a Land Rover Sport SVR through some mountain roads for about 45 minutes and was really disappointed in the brakes. They were very noisy. Not squeeky noisy, but just a lot of scraping/friction sounds (windows up) and then after about 30 minutes, the "thump thump thump" sound (that correlated with speed) when the brake pedal was pushed. I never had a lot of confidence in these brakes and this solidified my opinions. I guess it was brake fading, there were times where I just kept pushing the pedal without a real increase in stopping power, pushing all the way only triggered ABS once. Apparently, they were hot, but as I have said many times before, I have pushed 3800lb-4000lb cars this hard before in similar situations and never had the brakes let me down. It really affected the way I was driving and I had to leave myself a lot of room as a precaution. Still beat the Rover to the top though!

Not sure what is next. I can't justify pumping a lot of money into a car I am leasing for aftermarket rotors and pads on my dime, but I want to enjoy it while I have it. That is my dilemma now.

 

[itguy61]

Helo, if your theory about cementite and changes in metallurgy are correct then once this is happened it would seem you would see the problem pretty soon again after a re-bed due to differences in the metal over different parts of the rotor. I have seen several posts about people re-bedding after several thousand miles and having it reappear very soon. What I want to see is if anybody who puts aftermarket rotors and pads on sees the problem again. This is very frustrating, Kia is playing dumb on this and it does not look good.

Go over to the G-70 forums and they are starting to see the same issue. Being that Genesis is supposed to complete with Lexus and BMW I would think they would address this, not good publicity to have.

I understand your reasonable frustration given the car is a lease.

Mine is a purchase and I plan on keeping it 4 more years so if we learn that spending 6-7 hundred dollars for rotors and pads fixes it it is worth it to me.

 

[MisterMac]

I too understand not wanting to spend money an brakes for after market rotors when you are leasing.

Nonetheless, my AM rotor and
Pad combo is over 5,000 miles in and not a hint of vibration. I do not lose stopping power, even when going through our mountains.

 

[Helo58]

I think my next step will be to have to dealer put on another set of new rotors and try to source the Euro-spec pads. I'd love to hear the outcome of anyone that had the Euro-spec pads put on.