*update* to rapid brake pad wear in '03 E320 (10k miles) need help dealing w/ dealer
 

After taking the advice of the techs here, I did not bother to service the brakes on the car. It was taken the dealer. Just got a phone call from the dealer and it appears the rear pads are worn and causing the indicator lamp to turn on. The car was NOT driven with the parking brake on. That would be my first indication of rapid rear brake pad wear. However, the service advisor explained it that "the car was driven hard, and if the brake system detects rapid acceleration, it will apply the rear brakes."

I don't buy this excuse and I'm certainly not accelerating or driving the car hard. This is not my race car nor spirited weekend car. I already have an S2000 for that.

So what do I do? Eat the cost of the rear brake pad service and wait for it to happen again? I like to say I don't have the experience or knowledge to be called a mechanic but I'm no fool when it comes to the mechanics of a car.

TIA
-ardy

:confused:

I am not sure if your car has ASR or whatever they might call it where it brakes the driveline.

But I do know that my little brother changes his brake pads every 10k miles in the front, but not the back. I think usually you go through two to three sets of front pads to one set of rear pads.

I havent had a car with ASR so I dont know. Ask one of the 500E guys. Doing brake pads is easy, you can do it yourself.

Also, the parking brake has parking break shoes inside the rotor disc, the brake pads are a separate system working on the same disc. If you took the wheel off youd know what I am talking about.

The amber triangle flashes on earlier models when traction control is activated. It is usually accompanied by a chunking in the rear wheels as the offending wheels brakes are applied.

I need to keep an eye on the average mgh but so far it hasn't been abnormal. Something abnormal is the amount of dust and the grooves (lip at edge of each rotor) in all four rotors after 10,000 miles. The car was never driven hard, the tires are proof to that, they are wearing evenly and the shoulders aren't scrubbed. Foot wasn't on brake while driving. I can only deduce that the system is not performing properly and there's no way I can prove it.

-ardy

very good idea, I guess I'll go do some donuts in a field? lol...

The only explanation for the (REAR) pads being worn down are
either a SBC malfunction which may be hard to prove or diagnose
or the ASR function of ESP is kicking in, constantly trying to stop
spining rear wheels. Which is super hard on the pads.
I have seen lots of cars with higher HP or 4-matic in our area
that eat up rear pads during the rainy season in record time.
I had a client with a ML55 that used it for skiing. He did a bunch of snow and ice driving and the ETS was constantly trying to stop those rear wheels from slipping, needless to say we replaced the
rear pads at only 5500 miles.
His rear wheels were much darker from all the dust.
Being that your car has less than 12,000 miles and needs rear pads, If it were on my rack I would attack it as a malfunctioning
SBC system.
If you did drive like a maniac, your front pads would be toast long before the rears.
Driving with the parking brake on would just smoke the parking brake shoes, not the pads.
I would suggest you make NOISE to your MB Center about this issue and request this be fixed as well as replacing the rear brakes no charge.
Good luck
DR.D

I would assume Dr D would back me up on this:
Wear items under the new car warranty, such as brakes, wipers, bulbs, etc usually have a 12 month/12,000 mile special warranty coverage. It should take care of the brake pads if you are within those limits, and the dealer isn't claiming "vehicle abuse", (and if they are, I'd ask how they are coming to that conclusion). Your word against theirs, and you say the tires look good. You should be covered, but you really need an answer to why this happened to begin with. They are NOT obligated to replace them again in 10,000, just ONCE.

Gilly

Gilly and DR.DIESEL,

Don't these cars have a system to "dry" the pads and rotors by applying the brakes lightly when they detect wetness? I am not sure how this system works, or if it can work with only the rear pads, but if it is malfunctioning, I guess nearly anything is possible. In any case, I would think the car's performance would be suffering if you were driving around with the brakes lightly applied all the time.

vapors2k,

If you put the car in neutral and let it coast after getting up some speed, does the car coast or does it slow down a little faster than you would expect?

I agree you need to find out what the problem is, and I do not think it is confined to needing new pads. Good luck, Jim

The operation of (I believe it's called) Dry Stop is dependent on the operation of the wipers. It's not constant, it operates the brakes vry slightly and I believe the interval is every 20(?) minutes? I could look it up. It's a very very slight application, and is all 4 wheels.

Gilly

I think I had better look after the cars I have now as I'm not sure that I would ever want to update to any of the new models with electrohydraulic brakes, especially after reading of issues involved with changing the pads and the problem described here. I also was unimpressed with the pedal feel at lower speeds in the new E500 I had for an extended test drive.

That's nothing, you should hear about the brake fluid flushing procedure and recalibration afterwards. Whew! And they still expect it to be done every 2 years.

I just remembered the rotor-drying thing that SBC does is called "Dry Braking", I was thinking of "Soft Stop" before, which MB describes as a feature which eliminates the "annoying jerk" at the end of the stop. Last time I tried it the annoying jerk was still in the right seat when i came to a stop.

Gilly

Gilly,

Now that would be a feature even I would pay extra for! Jim

I will perform this to see if the car slows down too much. thnx!

*UPDATE*

When I put the car into neutral, the speed goes down normally, not abruptly as if the brakes were engaged. Whatever was wrong has apparently been fixed. I forgot to mention that after the car was serviced for the pad indicator light, the car has been a little quicker and seems as though those rear pads were dragging. How do I prove it? I don't think I can, and I had to eat the cost of the pads and labor ~ $220.00. :mad: