jave808

Hi
When I had my car serviced a few weeks ago, mechanic advised me that the brakes were nearly worn out.
My q is this - will I get a message due to the wear sensors to replace the pads/discs? Can I wait until I get the message? Or should I replace the pads and discs ASAP?

tjts1

Yes

cetialpha5

I believe you're supposed to get a message when they hit about 25% pad life left. If you do the pads before you get the message, you can reuse the sensor but they don't really cost that much. Also there's only one sensor on the front and rear so the sensor only tells you about one of the brake pads, the other 3 could be better or worse.

jave808

I thought that might be the case with a single front and a single rear sensor. Like you said the "unsensored" wheels may have less or more pad material.
I've decided to get the brakes done next Friday.

Odd Piggy

If my failing memory is correct, the older E320s had all wheels sensored, but that may have gone away with the demise of SBC.
Absolute minimum remaining friction material on any one pad is 4mm (0.156”). A good visual guide is when the pad surface is worn down to the thickness of the backing plate, it’s time to replace.
You are never wasting money keeping the brakes in top condition.

jonthondrkness

that is when they get the best traction when they get down to the metal on metal parts..

lthlc63

Well if the message doesnt come up youll def feel it when braking.
fcp euro has some decent kits front and back for cheap money.

ot1

yes it depends on your year whether or not you have a sensor on the left side, my 2006 did not and more wear occurred on the left side and tore into my rotor before the pads wore down enough on the right side to trigger the sensor.

stupid for mercedes to eliminate the left side sensor, the problem is if you are on vacation and it happens and mechanics are backed up in work, or they won’t deal with a mercedes or...sure if you live in germany its probably not a problem.

They were semi metallic pads, not sure why the left wore down 30% faster, but since then I only use ceramic pads.

ptkacik

Ha! Years ago, my wife and I borrowed her parents Volvo wagon and she asked me to look it over before we left town on vacation. The rear pads had worn down to less than a paper sheet thickness even though they had not touched metal on metal. A mind blowing catch. But even more so was that I drove a Porsche 914 then and had new front brake pads that fit exactly.

Luck beats skill,
Peter

Odd Piggy

It's the reason some of us are still alive.

rbm

When the pads wear down and trigger the sensor, is it mandatory to replace both the OEM pads and OEM rotors at the same time? I was told by a mechanic that this is a must because Mercedes designed these to be sacrificial.

If one was to switch to aftermarket ceramic pad / G3000 rotor kits available online, would I avoid this need to replace both parts (assuming its required)?

Odd Piggy

No. Check rotor thickness. If it’s within spec, just replace the pads and don’t have the rotors resurfaced (turned).
I’ve been replacing rotors on every second pad change with semi-metallic pads. On my one car with ceramic pads, the rotor is worn below minimum spec by the time the pads are worn. But the ceramic pads last three times as long, so it’s okay.
I don’t have experience with the aftermarket parts because I’ve stuck with MB pads and rotors.

jave808

I have now had my mechanic replace all 4 rotors, 2 brake sensors and front and rear pads. I used DBA rotors (Disc Brakes Australia) and Bendix Euro pads. I will monitor and see how long these all last.
My E280 has 2 sensors -1 front right and 1 rear right. So yes, if the left side wears quicker, you may be metal-to-metal before the sensors trigger.