Hi all,
I've read all the other threads about brake judder and things to check but I though I would ask about my specific issue...
The car is a 2007 CLK220 CDI Sport. I commute 100 miles in total per day, all of it motorway except about 5 miles. Partly because of the brake judder and partly because of 'driving for economy' I only use the brakes about 3 times each way. On the motorway I leave enough gap to the car in front I dont need to brake. This driving style is not likely to make the situation any better as I'm not using the brakes much, but I used to drive around town too and still the same.
The brakes have been juddering in some form for a long time now. I've tried to gradually eliminate the problem, sometimes it improves slightly for a while, sometimes not. At the moment braking is so 'harsh' every time I touch the brakes I just want to get rid of the car. Anyway...
First thing I changed front discs and pads. I took the car onto a rolling road when the judder first started, back brakes smooth, front all over the place. Turned out they were about at their wear limit anyway so seemed a decent place to start. While I was changing the fronts I took some measurements of the back - OK but would need doing soon. The judder improved for a few weeks (not gone completely, but a lot less noticeable). Then it came back.
I assumed this was now the back discs worn out so changed rear discs and pads. Again, possibly a small improvement (maybe just hope in my mind) for a week but then back to as it was before.
As things got worse I was due a service and MOT so took it into the MB dealer. Failed the MOT on worn front thrust arms. Got them both replaced and was also told to get the front tyres done as they were showing 'irregular wear' on the inner edge, probably because of the thrust arms. MB ensured me that changing these arms (at an extortionate cost) would solve the judder... no such luck. The paperwork from the service says they took the car for a road test and didnt notice anything unusual though... Hmmm...
Took the car to my local tyre place who sorted the tyres out OK and told me to monitor them as the others were comparable to a track-day car
While it was up on their lift with the tyres off I checked the runouts of all my discs which were all below 0.1mm total indicated runout. This was a relief as I wondered if I had warped the new discs. I was told the new tyres might solve the problem, but again, no such luck. Small steering wheel vibration when driving was sorted, but not the heavy judder on braking.
After a week the new tyres were wearing in the same place so got MB to do a full wheel alignment as I didnt want the new tyres to go the same way as before. Apparently there was nothing wrong, yet it took 4 of them 1.5 hours and they didnt charge me at the end which suggests they missed something on the service. Still, not going to complain at free alignment, especially from a MB dealer. Tyres now wearing OK which is a positive. Brakes still just as bad.
Now the brakes are so juddery that if I touch them on the motorway at 70mph its basically 'bang bang bang' as the car judders. Its very aggressive. Worse than ABS firing. Surprisingly, the harder I press the brake pedal, the smoother everything gets. Ie, slamming v. hard on the brakes its as smooth as you would expect and I stop in minimal distance, but just touching the brake is terrible at any speed. Even on a wet road I can't get the ABS to fire by slamming on the brakes, but then I never skid when braking either.
Anyone got any ideas. I wonder about wheel bearings but then during my MOT and service I got them to check it and they said everything was fine.At 60mph there is a bit of a high pitched whirr, so this could be a wheel bearing indication, or just the rear wheels on the road as unfortunately they still have the notorious V treads that are really noisy. My disks are shiny on the front but could I have a load of corrosion on the back of the disc?
As I say, I'm getting pretty fed up with this and though the car drives and accelerates excellently, the braking is taking the fun out and is wearing me down...
Any ideas would be greatly appreciated!
eblok
I've read all the other threads about brake judder and things to check but I though I would ask about my specific issue...
The car is a 2007 CLK220 CDI Sport. I commute 100 miles in total per day, all of it motorway except about 5 miles. Partly because of the brake judder and partly because of 'driving for economy' I only use the brakes about 3 times each way. On the motorway I leave enough gap to the car in front I dont need to brake. This driving style is not likely to make the situation any better as I'm not using the brakes much, but I used to drive around town too and still the same.
The brakes have been juddering in some form for a long time now. I've tried to gradually eliminate the problem, sometimes it improves slightly for a while, sometimes not. At the moment braking is so 'harsh' every time I touch the brakes I just want to get rid of the car. Anyway...
First thing I changed front discs and pads. I took the car onto a rolling road when the judder first started, back brakes smooth, front all over the place. Turned out they were about at their wear limit anyway so seemed a decent place to start. While I was changing the fronts I took some measurements of the back - OK but would need doing soon. The judder improved for a few weeks (not gone completely, but a lot less noticeable). Then it came back.
I assumed this was now the back discs worn out so changed rear discs and pads. Again, possibly a small improvement (maybe just hope in my mind) for a week but then back to as it was before.
As things got worse I was due a service and MOT so took it into the MB dealer. Failed the MOT on worn front thrust arms. Got them both replaced and was also told to get the front tyres done as they were showing 'irregular wear' on the inner edge, probably because of the thrust arms. MB ensured me that changing these arms (at an extortionate cost) would solve the judder... no such luck. The paperwork from the service says they took the car for a road test and didnt notice anything unusual though... Hmmm...
Took the car to my local tyre place who sorted the tyres out OK and told me to monitor them as the others were comparable to a track-day car
While it was up on their lift with the tyres off I checked the runouts of all my discs which were all below 0.1mm total indicated runout. This was a relief as I wondered if I had warped the new discs. I was told the new tyres might solve the problem, but again, no such luck. Small steering wheel vibration when driving was sorted, but not the heavy judder on braking.After a week the new tyres were wearing in the same place so got MB to do a full wheel alignment as I didnt want the new tyres to go the same way as before. Apparently there was nothing wrong, yet it took 4 of them 1.5 hours and they didnt charge me at the end which suggests they missed something on the service. Still, not going to complain at free alignment, especially from a MB dealer. Tyres now wearing OK which is a positive. Brakes still just as bad.
Now the brakes are so juddery that if I touch them on the motorway at 70mph its basically 'bang bang bang' as the car judders. Its very aggressive. Worse than ABS firing. Surprisingly, the harder I press the brake pedal, the smoother everything gets. Ie, slamming v. hard on the brakes its as smooth as you would expect and I stop in minimal distance, but just touching the brake is terrible at any speed. Even on a wet road I can't get the ABS to fire by slamming on the brakes, but then I never skid when braking either.
Anyone got any ideas. I wonder about wheel bearings but then during my MOT and service I got them to check it and they said everything was fine.At 60mph there is a bit of a high pitched whirr, so this could be a wheel bearing indication, or just the rear wheels on the road as unfortunately they still have the notorious V treads that are really noisy. My disks are shiny on the front but could I have a load of corrosion on the back of the disc?
As I say, I'm getting pretty fed up with this and though the car drives and accelerates excellently, the braking is taking the fun out and is wearing me down...
Any ideas would be greatly appreciated!
eblok
