Recurring one disk brake vibration (mistery?)
Thread Starter
Junior Member
Joined: Jul 2021
Posts: 42
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From: Quebec, Canada
GLK 250 Bluetec
Recurring one disk brake vibration (mistery?)
I have a 2014 GLK250 bluetec that I own since the past year. I love the car, but there is one problem I can not solve. I've been doing my own wrenching for the past decade on my cars but this is still a mistery.
I had slight front vibrations upon braking with the car when I bought it. Replacing the front disks solved that (with slighly used resurfaced disks). I also replaced the front connecting rods with an alignment. That solved the problem.
After a few months of light use I noticed some front left vibration when braking. I decided to do things rights and replace the rotors again for new ones and new pads as well. That fixed it but it came back after two months.
I replaced the disks again thinking that it was cheap disks + left connecting rod (was shot due to the vibrations) + new calipers + an alignment. That was fine for a month then it came back.
The vibration always come back slowly but it increases in a matter of a few weeks of usage. This is only on the front left side. I also replaced the rear disks and pads in the past and they've been doing fine since.
I'm not sure what could cause this ? It seems to be related to the left disk only. Every time my inspection reveal no spotting on the disk and they look brand new (well, they are only one month old afterall). I tought it could be related to calipers as well but that didn't help.
On a final note, I tow 3000 lbs with the GLK once per month, but I don't think that's related since all other disks are fine.
I had slight front vibrations upon braking with the car when I bought it. Replacing the front disks solved that (with slighly used resurfaced disks). I also replaced the front connecting rods with an alignment. That solved the problem.
After a few months of light use I noticed some front left vibration when braking. I decided to do things rights and replace the rotors again for new ones and new pads as well. That fixed it but it came back after two months.
I replaced the disks again thinking that it was cheap disks + left connecting rod (was shot due to the vibrations) + new calipers + an alignment. That was fine for a month then it came back.
The vibration always come back slowly but it increases in a matter of a few weeks of usage. This is only on the front left side. I also replaced the rear disks and pads in the past and they've been doing fine since.
I'm not sure what could cause this ? It seems to be related to the left disk only. Every time my inspection reveal no spotting on the disk and they look brand new (well, they are only one month old afterall). I tought it could be related to calipers as well but that didn't help.
On a final note, I tow 3000 lbs with the GLK once per month, but I don't think that's related since all other disks are fine.
Thread Starter
Junior Member
Joined: Jul 2021
Posts: 42
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From: Quebec, Canada
GLK 250 Bluetec
I did that before replacing the calipers and the temps were even (left and right). Still, I installed new calipers with disks a month ago but the vibrations came back.
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2013 glk 350
I used to have a sticking front caliper I noticed it by excessive brake dust on one wheel and my IR thermometer did show it to be warmer after fast stops, but I didn’t warp my rotor from it.
I used to warp my rotors on a different vehicle by quickly stopping from 50mph and the sitting on the brake, that allowed the rotor to cool in the one area of the pad quicker than the rest. Maybe your breaking style is partly to blame.
The rear pads on my glk seem to show 100,000 mile life , the fronts about 20,000, I think this is over biased to the fronts. Akibono pads should give a bit less braking force and Zimmerman rotors are harder which should also help reduce front force.
If you do stop from high speeds letting your foot off the brakes when you stop for 20 seconds might also help them
cool evenly.
If both your front brakes wear and dirty the rims the same they should be wearing the same. The only other idea is a bad proportioning valve.
Rotor warping is a common complaint here. I’ve had no problems with Zimmerman front rotors. but I also changed my breaking style.
I used to warp my rotors on a different vehicle by quickly stopping from 50mph and the sitting on the brake, that allowed the rotor to cool in the one area of the pad quicker than the rest. Maybe your breaking style is partly to blame.
The rear pads on my glk seem to show 100,000 mile life , the fronts about 20,000, I think this is over biased to the fronts. Akibono pads should give a bit less braking force and Zimmerman rotors are harder which should also help reduce front force.
If you do stop from high speeds letting your foot off the brakes when you stop for 20 seconds might also help them
cool evenly.
If both your front brakes wear and dirty the rims the same they should be wearing the same. The only other idea is a bad proportioning valve.
Rotor warping is a common complaint here. I’ve had no problems with Zimmerman front rotors. but I also changed my breaking style.
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From: WI
GLK 250
Welcome, Noxx.
You are in good company (unfortunately) since most of us have had brake warping issues. Before we bought our GLK250, the service records showed 3 front brake replacements in 49k miles. I thought nothing of it at the time, but I soon found out that it would need a fourth set.
I replaced the MB discs and pads with Stoptech Cryotreated discs and ceramic pads. Then comes possibly the most important part: bedding the new brakes in. You have to follow the manufacturer's instructions to the letter or you will likely have warping (or what feels like warping) issues again. I can't stress this enough: even with a OEM replacement set of brakes you must properly bed them in.
Suffice to say that was 50k miles ago and I've had no issues since. Good luck.
You are in good company (unfortunately) since most of us have had brake warping issues. Before we bought our GLK250, the service records showed 3 front brake replacements in 49k miles. I thought nothing of it at the time, but I soon found out that it would need a fourth set.
I replaced the MB discs and pads with Stoptech Cryotreated discs and ceramic pads. Then comes possibly the most important part: bedding the new brakes in. You have to follow the manufacturer's instructions to the letter or you will likely have warping (or what feels like warping) issues again. I can't stress this enough: even with a OEM replacement set of brakes you must properly bed them in.
Suffice to say that was 50k miles ago and I've had no issues since. Good luck.
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2013 glk 350
Stop washing your front rims until enough dust has built up on both rims to determine if one wheel is wearing more by being darker, with my bad caliper it was real noticeable which wheel was sticking
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Thread Starter
Junior Member
Joined: Jul 2021
Posts: 42
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From: Quebec, Canada
GLK 250 Bluetec
Indeed, I have new calipers (rebuilt) that were greased properly.
I'm kind of doubtful now that it is related to the disks. It's always the left side that vibrating after a few weeks. I forgot to mention that I have ceramic pads now, and that the car has a rebuilt title (previous front damage).
Could the hub be slighly warped and it affects the disk after a while somehow ? When I removed the previous 'damaged' disks, I could never find any brake pads spots or wear marks. They really look like new.
Finally, I drive very gently, without braking hard or riding the brake pedal. And when I occasionnaly tow my race car, my trailer has electric brakes to help.
I'm kind of doubtful now that it is related to the disks. It's always the left side that vibrating after a few weeks. I forgot to mention that I have ceramic pads now, and that the car has a rebuilt title (previous front damage).
Could the hub be slighly warped and it affects the disk after a while somehow ? When I removed the previous 'damaged' disks, I could never find any brake pads spots or wear marks. They really look like new.
Finally, I drive very gently, without braking hard or riding the brake pedal. And when I occasionnaly tow my race car, my trailer has electric brakes to help.
Last edited by Noxx; Aug 2, 2021 at 04:34 PM.
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From: WI
GLK 250
@Noxx
All bets are off, I'm afraid. If the front end geometry is off even by tenths of a degree, no telling how/where/whether the braking forces are being applied equally.
If new rotors AND pads don't help, and the alignment is as close to in spec as possible (difficult with a busted front end...), then you may just have to live with it unfortunately.
I forgot to mention that I have ceramic pads now, and that the car has a rebuilt title (previous front damage).
All bets are off, I'm afraid. If the front end geometry is off even by tenths of a degree, no telling how/where/whether the braking forces are being applied equally.
If new rotors AND pads don't help, and the alignment is as close to in spec as possible (difficult with a busted front end...), then you may just have to live with it unfortunately.
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2013 glk 350
I’m not a mechanic but once a mechanic put on 6 rebuilt starters on my car before buying a new starter. A rebuilt caliper ? Maybe you bought my defective one. I would never use a rebuilt caliper.
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From: Lac Ste. Marie, Quebec
2006 Alfa Romeo Brera, 2010 GLK350, 2018 BMW 640i GT, 1997 Subaru SVX, 2012 Moto Guzzi Norge GT8V
I have never bought a new caliper and I've never had a problem with a rebuilt caliper. That's in 45 years of driving.
I say the problem is the rebuilt title. Something is out of whack causing the issue. Was the car in a front end collision?
I say the problem is the rebuilt title. Something is out of whack causing the issue. Was the car in a front end collision?
Thread Starter
Junior Member
Joined: Jul 2021
Posts: 42
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From: Quebec, Canada
GLK 250 Bluetec
Yes, it was a front end collision, but I know the previous owner, and she had the car for 3 years without this problem. I also didn't have much vibration when I bought the car last year, but I decided to change the disks because they were very worn down.
Anyway, I think I don't have much choice than to try more expensive disk (cryo treated) and see...
Anyway, I think I don't have much choice than to try more expensive disk (cryo treated) and see...
Last edited by Noxx; Aug 4, 2021 at 06:19 AM.
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From: New Hampsha
'17 GLS450, '14 GLK250, Grandpa's Roadster
If the disk is the problem, you should be able to confirm that with a dial indicator. If it has run out, then you need to check the drive flange, too. If you have the problem with more than one disk then I'd look elsewhere for the root cause.
If it has floating calipers, make sure they are truly floating, not binding up. That could account for the fact that they are ok for a while, then it comes back.
If it has floating calipers, make sure they are truly floating, not binding up. That could account for the fact that they are ok for a while, then it comes back.
Thread Starter
Junior Member
Joined: Jul 2021
Posts: 42
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From: Quebec, Canada
GLK 250 Bluetec
Good point, I think that I will invest in a dial indicator. Can I measure the run out on the car with the GLK ? I know that the rotor has a holding screw, but it's on one side, thus it can possibly raise the opposite side little bit. I suppose the rotor centers itself when the wheel is mounted so it's not an issue while driving.
Thread Starter
Junior Member
Joined: Jul 2021
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From: Quebec, Canada
GLK 250 Bluetec
Ok I just want to report back.
I ended up buying a runout gauge and measuring the runout with a brand new disk on. Guess what, it's the hub the problem. It seems that the rust and scale is affecting the mating surface. In order to fix this without replacing the hub and bearing, I cleaned the surface as I could, then I bought shim washers on McMaster of various thickness. With the runout gauge, I compensated the runout by placing the washers between the hub and the disk. I've been running for +6 months now without any more vibration!
So the disks are not in cause but the hubs mating surface is critical. Especially for winter driven cars.
Good luck to all
I ended up buying a runout gauge and measuring the runout with a brand new disk on. Guess what, it's the hub the problem. It seems that the rust and scale is affecting the mating surface. In order to fix this without replacing the hub and bearing, I cleaned the surface as I could, then I bought shim washers on McMaster of various thickness. With the runout gauge, I compensated the runout by placing the washers between the hub and the disk. I've been running for +6 months now without any more vibration!
So the disks are not in cause but the hubs mating surface is critical. Especially for winter driven cars.
Good luck to all
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GLK350 2010 Sold C63 AMG 2012 Sedan Sold GLK250 2013
hi Noxx.
I'm having this problem now and I replaced my rotors 4 times in 12 months. I wish I saw this post before throwing all this money at this problem. How do you prevent said washer from falling when you remove the wheel lugs. Are they just held in place by friction? Can you share what diameters you purchased. I'll buy the same ones and take them to my mechanic. I just want to buy a range to be on the safe side.
I'm having this problem now and I replaced my rotors 4 times in 12 months. I wish I saw this post before throwing all this money at this problem. How do you prevent said washer from falling when you remove the wheel lugs. Are they just held in place by friction? Can you share what diameters you purchased. I'll buy the same ones and take them to my mechanic. I just want to buy a range to be on the safe side.
