SRich

Hello MBWorld,

I need your input on a situation with my GLK350's brakes and rotors. Here are some of the concerns based on facts. The vehicle was manufactured in January 2015. The front brakes and rotors were replaced in April 2015 at 1155 miles. I purchased the vehicle in June 2015 as a pre-certified vehicle from the MB Dealership with roughly 1500 miles. Six months later, January 2016, the front brakes and rotors were warped again and replaced within the 12 months/12,000 warranty. In December 2016, the rotors were warped again and replaced by MB. In March 2017, the rotors were warped again and replaced (this time as a courtesy) by MB. Last November 2018, the rotors became warped again and MB sent me away. I took my vehicle to a MB repair shop, and they in turn, sent me back to the dealership after reviewing the history of the rotors and breaks. This time I had to contact MB Corporate for guidance. MB Corporate along with the General Manager of my local MB Dealership have agreed to cover 1/2 of the cost this time around.

My understanding is there was a previous owner who, for some reason or another, chose not to keep this vehicle, and I'm wondering if it had something to do with the warped rotors being replaced at 1155 miles. I know the frequent replacements of the rotors are not due to normal wear and tear of vehicle. My MB Dealership has informed me that my warranty is over, and they refused to assist me with the issue of continuous warping of the rotors. My question is what would you do?

SRich

andreigbs

You're not the first, neither the last, with warping issues. Common theme on the portly GLKs with undersized brakes (in my opinion).

MB-brand discs will be a softer alloy than most others, which is why the issue rears its ugly head so often. In 91K miles, my GLK has gone through 3 sets of pads and rotors. You can have them replaced at an Indie shop with higher grade metal discs and ceramic pads like many have done, or replace them yourself like many (including myself) have done.

A side issue that may or may not apply: is the warping on both sides or just one? If just one, consider having that caliper replaced as well. That's where I'm at currently. I don't want to do a 4th set of pads & rotors that only last 5-10K miles before warping again. I'm living with it for now and trying to baby them until I decide to either go with bigger discs and pads from an AMG vehicle (see separate thread "AMG brakes on a GLK") or just replace the caliper(s) when doing the brakes again.

You're not alone, so there's that...

kombifan

Hmmmn I agree with the first reply. The brakes must be underpowered to create so much heat to cause warping so quickly.

If I were you I would use a better aftermarket rotors like ebc usr sport rotors or r1 concepts geomet rotors that are crossdrilled and slotted and match that wixthceramic pads.

Both those will cause less heat and give a lonnger lifetime than what you have experienced.


Still your situation concerns me. You don't feel a sticking caliper? Or over the top brake pressure?

mogulman

I replaced my pads and rotors with centric pads and centric cryo rotors at about 40k miles. I'm at 95k now and they are still working fine. I live in CO and use my car primarily to go up and down into the mountains from the city.

SRich

Thank you Mogulman! I'm checking on those parts now.

mogulman

BTW. I had some bad front brake warping before I replace my front brakes at 40k. The pads I used were the posi-quiet Cerramic.

SRich

Thanks again Mogulman! My Mercedes GLK350 was my dream car purchase; yet every year since the purchase there has been a rotor problem. I'm somewhat discouraged because this has never occurred with any other vehicles I have owned. If I'm to invest in brakes and rotors, I definitely want to get really good wear and tear out of them. I do not want a yearly brake and rotors expense. So, I thank you for the info on the Centric brakes and rotors. I'll mention these to my mechanic.

kombifan

Looking up the centric cryo rotors, i would highly recommend either the ebc jltimax or the r1 concepts drilled and slotted rotors.

The centric are still a solid disc, and with the issues yiuve been having you want to dissipate as much heat as possible to prevent any kind of warping.

Ebc rotors are solid. Expensive but really one of the best in the industry. I run them on a much heavier gl and I tow at times and they are flawless.

https://www.autoanything.com/brakes/ebc-ultimax-rotors

You can still pair them with the centric pads, but any ceramic pad manufacturer will do, and I personally trust the brembo ceramic or akebono pads a bit more...

The r1 concepts carbon geomet slotted and drilled rotors is a company I found through other forum members here who have bought them and reviewed them. The rotors aesthetically look solid, performance reviews seem happy and they're a great price. From what I read I wouldn't hesitate to order them for my next rotor job.
https://www.r1concepts.com/detail_ca...otor+silver+++

Hope it helps!

SRich

Thank you Kombifan!

Mmr1

Do you often slow to a rapid stop from 40-55 mph, I think the rapid heating then stoping at a light while the pad is in one place, on the rotor, warps them. I’ve since creaped along after stopping and have not warped a rotor in 15 years

NYCGLK

My original rotors lasted aroudn 60k miles.
Second MB set lasted 14k miles upfront and warped
I got Zimmermans from FCP Euro as they have lifetime warranty, cheaper than MB, too...have about 10k miles on them. So far so good.
Btw, swapping rotors is super easy, 1 hour tops.

NYCGLK

What you talking about I think is not leaving pad deposits on the rotor when coming to stop with pads hot. I think MB rotors are just made out of crap.

Mmr1

Could it be they are designed for stopping power vs a harder material that would not stop as well ? Sure you can get brake pads that don’t leave dust, I believe you also get a loss is stopping power. I’m just guessing as to the mb glk brake issue.

kombifan

Zimmerman makes the oe mb rotors for most models; so unless zimmerman knows something and changed the formula for their own brand rotors it should handle the same as the one with the star logo.

Zimmermans are great though!!

+1 on fcp euro!

mb rotors are way too soft...mb makes the rotors expendable....

NYCGLK

Considering they use the same rotor for left and right side (with angled vents) ... I don't think there is much more than the cost considerations.

SRich

Thank you for asking Mmr1. No, I cannot recall having to abruptly stop. I'm a "senior," cautious driver and I'm mindful of stopping at red lights especially since it was brought to my attention by the MB mechanic about three warped rotors ago. Because of that, I've been creeping along as you've mentioned. I've had my GLK350 since June 2015 and I have less than 40K miles on it.

Mmr1

What’s the wear pattern of the rear brakes, it could be a bad proportioning valve is putting to much braking to the fronts, you should have somewhere between 60 and 65% to the fronts, and the rears should wear out at about the same time. From what you’ve said your just wearing out the front brakes , if so it’s also strained and worn front suspension components. It should be under warranty.

I had an issue with my fronts, I first noticed a darkened, left front dusty rim, my left front caliper was sticking, I got a cheap IR thermometer and recorded the increased temperature after hard stops, and proved it to MB who fixed it free. (I also had a thermal camera) and that was further proof of a sticking caliper. Maybe it’s not the rotors or pads ! . If your not wearing out the rear brakes go see your mb service. If they refuse to help you will have to do what I did to prove it.

SRich

When my vehicle was under the brake warranty, MB replaced the rotors and brakes (front and back). Each time thereafter, the back brakes have been just fine. Back when the rotors warped the first time I was noticing an excessive amount of brake dust on the front driver's tire. I reported that to MB and they said the brakes were thoroughly checked, calipers were fine, and there was nothing to justify there was excessive brake dust. They did, however, clean my brake pads and put some anti-squeal lubricant on them, but it hasn't stopped the brake dust on that particular tire.

Mmr1

That’s like my issue, but I proved a bad caliper by Infrared thermometer and thermal imaging. Do rear brake pads last as long as front pads ?

SRich

I'm assuming they are fine. I was told by the MB mechanic that it was just my front brakes.

Mmr1

Your not being told the whole story, I think. It sounds like your rear brakes are ok, and not wearing much or at all, the front brakes are doing all the work, So the fronts are improperly balanced by the proportioning valve or your calipers are not fully releasing. You have proof with the left front wheel being more dirty of a bad caliper. You have to talk to your dealer and get a higher level of diagnosis . Like measurements of front and rear pads to prove the fronts are defective. A braking test. You have to figure it out , your dealer won’t. You have to know the wear rate, or thickness, of all the pads to know where to look. All the mechanic has been doing is replacing pads and rotors, it needs to be much more. From what you say, the rear brakes may be doing nearly nothing.

Joseglk

Nothing compared to what I have been through unfortunately. One of the same issues you are having but I'm to the point of getting legal advice maybe you should as well.. They fix my brakes 3 times in 6 months. Always acting surprised when I come in with the issue and then I find out-1st red flag- they can't even tell me if I'm getting refurbished parts or not. I finally asked after first new rotors lasted weeks. They don't have that information..That's very odd and concerning to me that a certified MB mechanic isn't aware of the status or age of the actual parts being used. They can tell you they are full price and that's about it. Pathetic imo. So the last time I get them done under warranty I leave the dealership like all the times before and halfway home I notice it says at the very bottom of receipt ( no more warranty work will be performed on the front brakes ).. so I originally paid full price for the brake work - Had to go in 4 times in 6months to fix what I paid for- then they just decided well we don't do quality work and can't supply quality parts that will last so no more warranty for you and in 1 month when they warp again you are gonna pay full price. Again. And when you pay full price, Again, no we can't even tell you if the parts you are paying a arguably high price for,Again, are even new or not. Isn't this a great deal! All the benefits of a certified MB mechanic. Gtfo. And we won't say anything to you we are just gonna leave that in the bottom of your paperwork it'll be a nice surprise for you next time they fail. ..im not having any of it.I purchased this car new and have had all maintenance at certified dealerships for the reason of warranty and faith that they know or care. They don't.. I won't ever go back to the dealership I'm never returning. Because MY MECHANIC WORKING OUT OF HIS GARAGE DOWN THE STREET OFFERS WARRANTY ON HIS PARTS AND SERVICE BECAUSE HE BELIEVES IN THEM-CERTIFIED MERCEDES BENZ DEALERS DONT
​​​​​​ I swear I'm gonna make that a bumper sticker and bring my car in for another months worth of brake service at full price. smfh
Anyways I email corporate knowing what is coming already. They reply with the answer to absolutely none of my questions or concerns and it really was shocking to me the replies..I will post pics of the emails with MB and my service records later this is just a rant after seeing your post. I'll have the entire thing more detailed because it goes along with more seriously not so legal replies from service advisors and MB regarding the airbag recall taking forever and them just being cool with a customer driving around for years knowing the airbag might actually kill him as he drives in Florida rush hour twice daily literally witnessing several serious crashes during this time. /Oh and did we mention his brakes are horrible and constantly failing and we absolutely don't warranty or stand behind the service or parts he receives. Like i said the entire thing will be posted soon. I have been told I have a case for something. I really tell people if I die in a car accident take this file with the proof and records of all this I guarantee it won't work out for them iv been almost begging them for help just to have BRAKES and AIRBAGS that work..kind of a big deal. never have I asked anything for free or been disrespectful in any way... I'll end by saying I have actual email from MB corporate stating if I want parts or service that are guaranteed to be new and warrantied to go somewhere else they cannot provide that for me at this time. In another email I simply ask them for advice. I asked what would you do after all of this and the situation I'm in? I'll give them credit they answered honestly and said No in my situation they would not return to a certified Mercedes dealer. I replied thank you for the honesty can you at least tell me where I can find parts and service that live up to the Mercedes Benz name? And I never heard from Mercedes Benz again....
to be continued

NYCGLK

Just replaced my 3rd set of rotors. This one set lasted 17k miles before the same vibration appeared. Yep, rotors are warped again. The car is over 10 years old with over 101k miles.
To recap:
-Original rotors were taken off at 71k miles (they had lots of build up and essentially stopped wearing, but also were not very effective)
-Next set of MB rotors lasted ~13k miles
-Next set of Zimms lasted ~17K miles

I'm using Zimmermann rotors for 150 bucks (for a pair) from FCPeuro, so the current set will go back to them under lifetime guarantee.
I do my own work. One nice thing with frequent replacement, it's easy to take rotors off.

Once pads wear off, I'm going to try something other than MB crap. Buying genuine MB brake parts was a mistake.

mikefili

Very possible not warped rotors at all. Disc breaks work by having a transfer layer of pad material transferred to the rotor surface. This pad layer deposited on the rotors makes it all work. Mostly “warped rotors” are an uneven buildup of pad material which causes the friction to constantly change as the rotor goes through its rotation and will cause the pedal and steering wheel to pulse. Try this brake bedding procedure.
Go on a very quite street or highway, speed up to 60 or 70 and apply the brakes as hard as you can without locking up to 10 or 20
mph, do not come to a stop, repeated this as many times as needed till the brakes fade out due to high heat, again do not bring the car to a stop during this process, once the brakes have overheated and faded accelerate back to normal driveling speed and let the brakes cool off while driving on their own, you will smell burning pad material, not to worry. After 20 minutes or so of driving cool down time your brakes may surprise you by working perfectly with no pulsing now that you have reapplied a new transfer layer to the rotors while cleaning off the old uneven one.the whole trick is to try not to apply the brakes at all as you drive normally to allow the brakes to cool.

NYCGLK

I used to think this and did exactly what you say the first time around and shuddering got much worse. When I took the wheels off you can see the runout of the rotor by looking at the pad area. Rotor would be touching the pad an then there would be light between rotor and the pad as you rotate it...so call it 2-4mm of run out. Second time around the same thing.