My lease is up in May on our '14 GLK350 and we are thinking about purchasing it as not too enthused about going to a turbo 4 in the GLC however two issues are making us have second thoughts.

1) has 31k miles and front rotors have been replaced twice under warranty due to warping (is this a common problem? - didn't see a lot of posts when searching

2) the brown leather on the steering wheel has discolored and turned ashy, only remedy is to pile on a bunch of leather conditioner - dealer says this is due to wife's hand lotion and that an MB rep would have to investigate if we wanted it replaced (sounds suspicious). Any experience with these two issues would be appreciated. thanks.

 

There have been posts here for the rotor warping. Warping comes from excessive heat. That comes from aggressive driving and many hard stops. The car weighs over 2 tons but drives like a small economy. I believe that isn't an inherent problem in the car, but rather on the driving style. No problems with my steering wheel and hadn't heard of that issue before. Likely dealer is correct.

 

Thanks. This is helpful, my wife is an aggressive driver so that makes sense. Will have to talk to her about the industrial strength hand lotion though. Hah!

 

You can keep your car or I would really consider the GLC. The turbo 4 is great.

 

Those rotors don't warp. That's myth or a way to get customers to keep changing rotors at 4x markup. What's likely is happening is you have pad material build up from improper bedding in. My original rotors lasted 70k miles, and they had excessive build up of "crap" where the car would vibrate under heavy braking.

 

Left is inside, right is outside. Those are original that came in 2009. Pads were at like 50%. By looking at this, you would think my brakes sucked but they worked ok for SUV. New pads/rotors definitely have better bite. duh

 

Sorry NYCGLK. Any rotor can warp given the right circumstances.

 

Unfortunately, it is an inherent problem with the rotors and is a well known issue on several MB models. It is not always due to abuse or overheating. My first set lasted 1500 miles while I was still breaking the car in. In any event, a set of breakers should be able to stand up to whatever the car dishs out in any road, not race, situation. I'm on my third set of rotors and I went with aftermarket units and they have lasted three times longer than the MB units. Same driver with different results means the rotor is the issue. As to those that say it's the pads causing the issue, I wish I had taken pictures of the potato chip that was my stock rotor after only 1500 miles. Next time it happens try Centric Stptech rotors for a much cheaper and better rotor.

 

550x2, I had an issue like that on an old Honda Accord. The stock rotors would only last about 15K. Final just bought a set of OEM replacement Brembo rotors. nothing fancy. Boom! Problem solved.

From what I understand. The issue is two fold.
1, To save weight the OEM designs the rotor to be as light as possible and still stop the car.
2, Everyone likes wide wheels and this creates an air flow issue, Which can translate into a lack of cooling. Add an aggressive driver & that's usually enough to send it over the cliff.

I assume that my 2014 GLK250 has the same rotors. But I drive the diesel the way it was designed to be driven. Perhaps that's why I average 40MPG and at 37,000 miles the brakes look nearly new.

No issue with the steering wheel either. Other than one small scratch from the wife's wedding ring.

 

The brakes is nothing new :
https://mbworld.org/forums/glk-class...80-brakes.html

 

Good thought with the aftermarket units. Stoptech + my local euro mechanic sounds like a plan. If we keep it and it happens again I'll probably go that route. Doesn't make sense that MB would have replaced the rotors twice under warranty if it were really a pad issue. The dealer has really been great about it, no hassle just replaced when brought in no questions asked.

 

where are you getting your information from? We are not driving race cars here, it's street driven car with pretty tame drivers. Look at my rotors that came off after 70k miles, the heat was never an issue there.

If you are truly going to overheat your brakes, first you will wear out or melt the pads very quickly, second, your rotors will have discoloring and stress cracks from the heat. GLK has pretty big pads and big rotors upfront to dissipate the heat (in fact, they are as big as ones on my porsche that sees plenty of track time). And there are these vents in the rotors for cooling so wider wheels have zero impact. Whether tire is 225 or 295 there is no direct air going onto the rotors.

 

NYCGLK, From lots of experience, Having built a few hotrods and Arizona Automotive Institute. Depends on the wheels. Lots of manufacturers do factor in wheel design in how much air flows through the wheel. Your Porsche was designed for high speed, So it has brakes to match. But there is air flow in any wheel.

The case of my Honda Accord. I didn't drive it like a nut job. Come on it's a Honda and as such is a very reliable but very boring & uninspiring car to drive. But it had issues with the rotors warping. After I put on the Brembo's, The problem never resurfaced. So it was clearly a design issue of saving not only a few ounces, But a few dollars as well by putting on thin rotors. It's the game most if not all manufactures play. So the limit of being acceptable & failing from heat is far closer together on a normal street car than it is in a car designed for high speed.

I not sure what your experience is, but I can tell you all you have to do is look at some of the GLK's on this forum. And you can see that there are a fair few that want more power, Speed, Lowered, Oversized wheels & tires. There was even a guy last week that was asking about mods for more HP from a bloody 2 litre diesel in his GLK250. So some folks do drive their SUV's like they are sports cars. It kind of comes with the territory of the untrained "I got my license from a cracker jack box" modern American driver.

However one doesn't have to drive fast to drive aggressively. Especially when it comes to braking. Two cars can be going the same speed, side by side. But the more aggressive drive will wait until the last possible second to hit the brakes. So they hit the brakes much harder. Now do this at not only every light in town. But at every off ramp when exiting the highway at 75MPH. Such was the case of the OP who even said his wife was an aggressive driver.

When I was driving in the Caterham super 7. You bet I drove fast & often in the German countryside, as that's what it was designed to do. But in my GLK diesel or our diesel motor home. I drive them like they were meant to be driven. Hence my stellar fuel economy from the GLK.

 

I won't argue as there is no point, but I will add two comments:
-The way Porsche address cooling is by adding air scoops or deflectors to direct air to the rotors.
-When I did bedding of the new rotors and pads on GLK, I did about 10-15 panic stops from 50mph to almost zero, before the pads started smoking (literally I saw smoke coming off). Then drove a bit more to let them cool and parked the car. This resulted in a nice smooth braking with very good initial bite. I can see where aftermarket rotors might help, if they have holes or slots that help to keep the pad area clean.

 

Warping can also occur with uneven heating and cooling, as when water gets on the rotors in rain or winter conditions.

 

I used to live in an area that was highways but with stoplights every few miles, I'd drive 60 mph and have to slam on the brakes. Brakes get hot, and pads sit in one place on the rotor, cooling that area faster. That's how I warped a set, from then on I'd put the car in neutral and let off the brakes or slowly move as to not cool one area of the rotor. Since then my rotors don't warp. Yes crappy MB rotors, and poor driving habits equal warped rotors.

 

Argument? Wow! I didn't realize this was an argument. I thought this was an automotive forum where we freely discuss all things automotive, with (of course) a bias towards MB's.

 

Yup, there is no argument.

Warped rotors on road cars is a fallacy. The real problem is uneven transfer of pad material to the rotors causing uneven friction.

Have a read:

http://www.stoptech.com/technical-su...nd-other-myths

I would not be surprised to learn that the brake hold function in the glk is a contributing factor given that you have to press harder than normal on the pedal to engage the hold. Using the hold after hard braking with hot brakes is the perfect recipe for uneven pad transfer to the rotor.

 

My wife is about to get her second set of front rotors. Her GLK has 11K miles. No "driving habits" besides tracking the thing should ever be warping rotors. People saying "it's driving style" is bull****, full stop.

 

the GLK factory brakes are crap, they squeak, has massive amount of dust, and warp easily. I will definitely go aftermarket soon.

 

Just my .02, but in 80k miles on my wife's 2008 CRV (which we bought new) we didn't have to do any brakes, at all, which we disclosed when we traded it in. We had a set on her 2014 GLK (bought new) warp after 20k and then they just warped again, at 32k. Going back in and I tend to side on the 'it's the materials, not the driver' side of this 'debate.'


I think in our specific case the calipers are ever so slightly occasionally dragging on the rotor. I complained about this the first time and they didn't buy it, but here we are again.

 

Who makes the best rotors and pads?

 

I just bought a full set of Brembo rotors and matching pads, but will be using Akebono Euro Pads in place of the Brembos. I previously used Centric rotors on my toyota before and I didn't like them because they started to show wear really quickly.

As for the best hardware, its hard to say as there are so many variables. Some things to take in consideration:

-Type of Brake Fluid used
-Using Hard or Soft Pads
-Using Metallic or Ceramic friction material pads
-Correct installation including torquing hardware correctly
-Are you using brake quiet paste/grey brake paste?
-Brake lines free of air?
-Were the pads installed without any oil contamination?
-Do rotors have slots, dimples, flat, or holes?
-proper bedding in procedure

So if you buy the most expensive rotors and pads, but don't install them correctly they will not perform great. Or using crap pads on expensive rotors the pads will eat up the rotors. A common issue is not bedding correctly or riding the brakes.

For the majority of GLK owners, a typical inexpensive smooth rotor and a ceramic pad from EBC or Akebono will do great. Its not necessary to spend a ton of money on wear items.

 

got all the Akebono and Brembo hardware in:



The brembo rotors are wayyy nice fit and finish out of the box than the Centric I used previously.

 

Quick update - when the did the 'brakes' at 20k they are telling me they only did the rotors. The pads apparently were not changed and now the pads have chewed up the new rotors at 12k miles. They are also telling me that the rear brakes need to be done.


How did you folks who had this covered under warranty get this covered under warranty when the warranty is only 10k miles? I know some feel otherwise, but my wife is NOT riding these brakes hard and neither of us have ever warped rotors in our lives on any car except this one (even our 2013 GLK was fine, my 2013 E550 is fine, etc.). There is something else going on, either sh*tty MB parts or calipers dragging on the rotors creating excessive heat, etc.