Brian_R170

My wife's '04 E320 Wagon with 31K miles has the "Brake Wear" indicator showing. I checked the pads the the fronts look like they've got at least 30% remaining, probably more. The rears look like they've got less than 10% remaining, though.

I did a search and saw that at least one other poster had his rear brakes wear the same way (35% on the fronts when the rears were tripping the brake wear indicator). I've never owned a vehicle where the rear pads didn't outlast the fronts by at least 2x, so this seems abnormal to me. Are the stock rear pads that thin or is the SBC applying much more pressure to the rear?

One interesting thing is that my front rotors have smooth, even wear while the rear rotors are very grooved, and I noticed the grooves well before 10K miles.

KShortill

I had the same situation recently, at only 28,000 miles, on a 2004 E500 4matic wagon. Perhaps it is something to do with the wagon?

paulv

... for the W211's due to the SBC and other braking functionality. Another thing is that you should visually check your brakes for wear and not wait for the MFD to tell you. These cars have floating calipers, and these type of calipers are known for uneven pad wear. The brake pad sensors are only on one pad per wheel except for the driver's side rear wheel. The pad without the sensor could easily wear down before the sensor'd pad causing rotor damage and you wouldn't know it until it was too late.

Regards,

paul...

Brian_R170

Would a set of Brembo rotors with Porterfield RS-4 pads help them to last any longer?

I found a website that lists the retail prices for the OEM rear rotors as $72 each and the pads at $65 for the set. That's $209 in parts, plus about 2 hours for labor at $95/hr. I'm guessing the rear brakes are going to run at least $400 from the dealer.

Brembos + Porterfields should run around $300 and I'm fairly certain I can do the job myself (with copies of the WIS pages in PDF format).

jimbo1mcm

The rear pads are much thinner. I have a set of new front and rears. When you hold them up next to each other, you can see the difference.

paulv

I put the Brembo/Porterfield combo on my rear brakes, but I have 6Kmi on them so it's too early to tell. If you decide to do the work yourself (it took me about 2hrs) you may want to also buy a set of parking brake shoes and change those out too -- I wish I did. I'll be doing my fronts soon -- they have 70Kmi on them!! No secrets to the long life -- 90% of my driving is highway.

Regards,
paul...

billh556

Don't know if the wagon or the 4Matic system contributes to this, but the dealer put new rear pads and rotors on mine at about 15k miles. Needed new rear tires then too, even though the fronts were in much better shape. Service advisor said that was common on the 4Matic cars. Now have 38k miles and need new rear tires again fairly soon, but the brake pads checked ok during a recent service visit.

BlueMonk

New rear pads / rotors on my E320 at 22,000 miles. Supposedly front was fine.

mbbodytech

Supposed "excessive" rear pad wear can be attributed to the SBC system, as it brakes whatever corner needs it the most. This is a contrast to the usual brake system where the bias is fixed and always stays "front heavy"

It's the technology at work for you! However, it would probably be good for Benz to increase the amount of pad avaiable at the rear...or should I say it would have been good to do it in the first place, as the caliper would have to be redesigned to make that happen, and I don't think that will happen.

konigstiger

DTB P-B-42.10/48 JUL04 – Increased rear brake pad wear.

Rear pads were revised (part # A004 420 44 20) as of 05/04 production to address rear pads from prematurely wearing and/or the rear brake pads wearing prior to a warning message in the IC being displayed (part # A004 420 44 20).

newton22

I also noticed this last time I swapped the pads.

I attributed it to ESP. Since I have a heavy foot, even in rain, I break my rears loose many of the times, and ESP tries to regulate traction by applying rear braking power.

mkaresh

I just learned that this can be the case recently. Seems a bad way for manufacturs to save a few bucks.

LAZARU5

Whatever was changed seems to have worked. I have 56K+ miles and the original pads in both the front and rear still have plenty of life remaining.

khaug

Rear pads do less work than the fronts, hence it's normal for the rears to be thinner. This has been the case with all new cars I've had for the past umpteen years. Manufacturers tend to set F/R pad thickness so that both need replacement at the same time.

At 22K miles, my front and rear pads look to be less than 50% worn, and the rotors look like new. Probably some of this is due to the type of driving I do (mostly in the country, or on Interstates). However, I'm careful to look ahead and slow down when I need to without using the brakes. This has a major impact on pad/rotor life. It also enhances mpg, as you're off the throttle earlier.

If you drive with your vision aimed 50' in front of the car and brake hard coming up to red lights, stop signs and such, you're going to pay the price!

Regards,

SAguirre

My 1991 had a similar front to rear rotor proportions, but the W211's brakes seem to be much larger. However, I would get about 45k miles on the front pads on my 300E and I replaced the rear rotors and pads because the rotors warped at about 105K. The pads were not worn very much.

What I have heard is that in the new Mercedes cars (especially with SBC) the rear brakes can do as much as 50% of the braking. Apparently this reduces the amount of nose dive and improves handling on curves. The second a rear wheel locks while braking, the system will send more power to the front. Also, the SBC will automatically send more power to the front brakes at higher speeds.

My dealer told me that the rear pads and maybe rotors are now a bit too small for the amount of braking they are doing. He also said that his clients who do more highway braking tend to wear out the fronts and people who drive in town more wear out the rear way sooner because of the increased braking being done by the rear at slower speeds.

With all this being said. I just had a "service D" and my brakes are at 65% all the way around. My car had about 24k miles on it when I brought it in. So this car is tracking at the same rate as my 300E. I expect to get about 40K to 45K out of the fronts, but it looks like the rears will also be worn and to be replaced, in my 300E the rears lasted forever!

I drive around town all the time, but not a high speeds and I always look ahead. However, I will drive on some highway trips and drive 800 miles and only stop to get gas. This is the same way I drove my 300E. So considering how other people's brakes have been wearing I guess I am really doing great!

Steve