E-Class Front Brake Wear Sensor
Thread Starter
Super Member
Joined: Nov 2001
Posts: 864
Likes: 1
ML
E-Class Front Brake Wear Sensor
Yep, after finding out two weeks ago that the rears don't have a wear sensor, just yesterday the wear sensor light came up on the dash - meaning the front ads are nearing their end of life. For moderate city driving, how much pad do I have when this light shows up? I have another 3K before next service and I'd rather wait and do it then. Soemhow, I doubt that the pads will last 3K. What's your best guess average?
Member
Joined: Aug 2003
Posts: 103
Likes: 0
From: Fayetteville, GA
1987 300D Turbo, 2007 ML63 AMG
Pull the wheels off and visually inspect the pads. The original pads are beveled on the side so you can slide your finger nail under the edge of the pad. If you can, then there is still plenty of pad remaining. However, the important thing is to make sure that both pads, inside and outside are wearing evenly. If they do, that tells you that the brake caliper is floating and functioning normally and that there should not be an immediate problem developing. I do this check every time I rotate the tires, about every 6,000 miles. I now have over 66,000 miles on the brakes (and tires) and hope to make it to 100,000 miles before replacing the pads, not the tires. In your case I would ask myself, how many miles ago were the brake pads installed. If this was 30,000 miles ago, then 3,000 miles more would mean an additional 10% of wear.
Banned
Joined: Apr 2002
Posts: 708
Likes: 0
From: Kansas
96 E 320 and 87 560 SL
When my brake sensor indicated brake pad wear I went another 1k and when I replaced the pads I had to relace the sensors as well. The sensors are imbedded in the pads and if you replace the pads right away you can reuse the sensors. If you put the brake job off the rotor starts to cut into the sensors. All this happens long before the pads completely wear out (read metal on metal grinding noise)
Member
Joined: Aug 2003
Posts: 103
Likes: 0
From: Fayetteville, GA
1987 300D Turbo, 2007 ML63 AMG
Good post, bigtire. But pray tell, whatever did we do before we had sensors? My suggestion would be, if it's a new car or if the old girl is going to drive your car, then better make sure that you replace the pads before the sensors get ruined.
Member
Joined: Aug 2003
Posts: 103
Likes: 0
From: Fayetteville, GA
1987 300D Turbo, 2007 ML63 AMG
brake pads
Darkmann, if you have original brake pads, they should be beveled so you can push your fingernail in between the pad and the rotor. I think as long as you can do this, there is plenty of brake pad remaining for another 3,000 miles - so I would guess. I just ran into the same problem, brake pad wear light cam on, I pulled off the wheels and saw where the pads were still beveled. I put the wheels back on and ordered a set of new front brake pads. Now I have to figure out how to do the replacing - myself! The pads where a little over $40, I'm not going to have the rotors turned and I do not foresee any problems, unless somebody can tell me what to look out for. By the way, I have over 75,000 miles on the car, original brakes and original tires - and I just turned 75 myself. Maybe that will help to explain it. :-)
MBWorld Fanatic!
Joined: Nov 2001
Posts: 3,861
Likes: 3
From: Jacksonville Florida
209/W210 Estate /W211 modded by MBENZNL
Re: brake pads
Originally posted by fritza2tt
Darkmann, if you have original brake pads, they should be beveled so you can push your fingernail in between the pad and the rotor. I think as long as you can do this, there is plenty of brake pad remaining for another 3,000 miles - so I would guess. I just ran into the same problem, brake pad wear light cam on, I pulled off the wheels and saw where the pads were still beveled. I put the wheels back on and ordered a set of new front brake pads. Now I have to figure out how to do the replacing - myself! The pads where a little over $40, I'm not going to have the rotors turned and I do not foresee any problems, unless somebody can tell me what to look out for. By the way, I have over 75,000 miles on the car, original brakes and original tires - and I just turned 75 myself. Maybe that will help to explain it. :-)
Darkmann, if you have original brake pads, they should be beveled so you can push your fingernail in between the pad and the rotor. I think as long as you can do this, there is plenty of brake pad remaining for another 3,000 miles - so I would guess. I just ran into the same problem, brake pad wear light cam on, I pulled off the wheels and saw where the pads were still beveled. I put the wheels back on and ordered a set of new front brake pads. Now I have to figure out how to do the replacing - myself! The pads where a little over $40, I'm not going to have the rotors turned and I do not foresee any problems, unless somebody can tell me what to look out for. By the way, I have over 75,000 miles on the car, original brakes and original tires - and I just turned 75 myself. Maybe that will help to explain it. :-)
http://www.mercedesshop.com/e_class_brakejob.htm
MBWorld Fanatic!
Joined: Jun 2002
Posts: 3,559
Likes: 4
From: Las Vegas, NV USA / London, UK
GL320CDI / C63 Edition 507 Coupe (EDP) / E63 S (on order) / G500 / Smart Brabus
If you are relying on the brake sensors, you can wait until your brake replacement warning light GOES OFF before you replace the pads. 
(Seriously... there is brake pad material UNDER the sensor... but if you are negligent in replacing your rotors the lip on the rotor might touch the pad. No big deal really.)
-s-
(Seriously... there is brake pad material UNDER the sensor... but if you are negligent in replacing your rotors the lip on the rotor might touch the pad. No big deal really.)
-s-
Trending Topics
Member
Joined: Aug 2003
Posts: 103
Likes: 0
From: Fayetteville, GA
1987 300D Turbo, 2007 ML63 AMG
brake pad replacement
Thanks, all. Really, once you do one side, you realize how well engineered this car is. The only additional tool I had to get was the 7 mm Alan wrench. Observations: the lip on the outside edge of the rotor touches the sensor way too early and that sets off the warning light. Now I am tempted to disconnect the warning sensor and just observe the pads when I rotate the tires. When they get down to one eighth of an inch, it is time to look for brake pad replacements. Part of brake pad replacement should also be a change of brake fluid. But, rather than forcing the fluid back into the master cylinder reservoir, would it not make more sense to open the brake bleed valve and allowing the fluid to escape? Then drawing out, perhaps with a sysinge, the remaining brake fluid from the reservoir, replacing it with fresh fluid before bleeding the brakes thoroughly afterwards?
MB World Stories
The Best of Mercedes & AMG
8 Oddball Mercedes Ideas That Actually Made it to Production
Verdad Gallardo
Dubai Tuner Gives the Mercedes G-Class An Entirely New Look
Verdad Gallardo
Six Gift Ideas Your AMG Loving Dad or Grad Will Cherish
7 Craziest Things AMG Gas Ever Built
Verdad Gallardo
New Electric Mercedes-AMG GT 4-Door Coupe Unveiled: 10 Things You Need to Know
Verdad Gallardo
6 Mercedes Models That Did NOT Age Well (But Are Somehow Still Cool)
Verdad Gallardo
Manual Mercedes? 6 Times Sindelfingen Let Drivers Have All The Fun
Verdad Gallardo
Mercedes SLR McLaren 722 S Is Extremely Rare Example Modified by McLaren
Verdad Gallardo
8 Classic Boxy Mercedes Designs That Have Aged Like Fine Wine
Verdad Gallardo
MBWorld Fanatic!
Joined: Jun 2002
Posts: 3,559
Likes: 4
From: Las Vegas, NV USA / London, UK
GL320CDI / C63 Edition 507 Coupe (EDP) / E63 S (on order) / G500 / Smart Brabus
Re: brake pad replacement
Originally posted by fritza2tt
Thanks, all. Really, once you do one side, you realize how well engineered this car is. The only additional tool I had to get was the 7 mm Alan wrench. Observations: the lip on the outside edge of the rotor touches the sensor way too early and that sets off the warning light. Now I am tempted to disconnect the warning sensor and just observe the pads when I rotate the tires. When they get down to one eighth of an inch, it is time to look for brake pad replacements. Part of brake pad replacement should also be a change of brake fluid. But, rather than forcing the fluid back into the master cylinder reservoir, would it not make more sense to open the brake bleed valve and allowing the fluid to escape? Then drawing out, perhaps with a sysinge, the remaining brake fluid from the reservoir, replacing it with fresh fluid before bleeding the brakes thoroughly afterwards?
Thanks, all. Really, once you do one side, you realize how well engineered this car is. The only additional tool I had to get was the 7 mm Alan wrench. Observations: the lip on the outside edge of the rotor touches the sensor way too early and that sets off the warning light. Now I am tempted to disconnect the warning sensor and just observe the pads when I rotate the tires. When they get down to one eighth of an inch, it is time to look for brake pad replacements. Part of brake pad replacement should also be a change of brake fluid. But, rather than forcing the fluid back into the master cylinder reservoir, would it not make more sense to open the brake bleed valve and allowing the fluid to escape? Then drawing out, perhaps with a sysinge, the remaining brake fluid from the reservoir, replacing it with fresh fluid before bleeding the brakes thoroughly afterwards?
I prefer to flush the brakes every two years or less, using either a MityVac or a pressure bleeder. I find that bleeding with the master cylinder can cause premature failure of the master cylinder.
I generally alternate ATE blue and gold fluids so that I can see when the system has been completely flushed (the color of the fluid changes at the bleeder valves).
-s-
