hi,
The other day a "check brake pad wear" message came up on my dashboard, my 2018 E63S has 13,460mil / 21,536km on it, I took a quick look at the front brake pads through the wheel spokes, they seemed in good shape, I figured I might as well order a new set of brake pads front and rear and when I get a chance i will further investigate the pad wear and why the “check brake pad wear message” showed up, once I received the new pads I visually compared their thickness with the ones on my car without removing the wheels, the front pads seemed new, the rear pads were worn out with little meat left on them, I couldn’t understand how is it that at 13,460mil / 21,536km the rear brake pads are already worn out while the front look relatively new, I’m the first owner and the car was never tracked or even driven hard, all of the miles on it are freeway miles, I did some research online and it turns out that the traction control system on the E63’s gets very involved to prevent a tiny bit of spinning on the rear wheels by using the brakes which is why they get worn out pretty fast. I have decided to replace the rear pads by myself even though I was a bit worried that since the car is an AMG with a ceramic brake system that’s so very expensive things might be more complicated than the usual standard procedure carried out to replace rear brake pads, gladly it turned out to be a piece of cake. I put together this DIY step by step rear brake pad only replacement procedure hoping it will help someone who might be looking into doing this type of job on their own.
First you will need to retract the parking brake cylinder, this can be done through a hidden menu that can be accessed using the steering wheel controls, to get to the hidden menu you will need to push the start engine button once (without pressing the brake lever), then the left home button and ok button one after the other. This will open the hidden menu, select “brake pad replacement” and then press ok to enter “fitting position”.
Now you will need to loosen the rear wheel lugs, lift the car up and remove the wheel.
Brake pad replacement procedure:
1- Pry off the caliper cover.
2- Disconnect the parking brake electrical connector by pressing the locking tab and pulling the connector out.
3- remove the two cables from the holding clips so that the caliper can move freely.
4- remove the brake pad wear sensor by pulling it straight out, no need to replace it if the remaining brake pad thickness is more than the thickness of the sensor pin.
5- undo the bottom caliper bolt using a 12mm wrench and a 17mm wrench.
6- now the caliper should be free to move on the top bolt axis, lift the caliper up and remove the brake pads, they easily slide out.
7- remove the brake pad retainer clips, you can pry them out using a flat screw driver.
8- compress the caliper piston using a brake piston tool.
9- the installation procedure is the reverse of steps 8-1.
10- exit the “fitting position” from the hidden menu.
New pad thickness 11.5mm.
Old pad thickness 3.5mm, that’s 30%, next time I will be replacing them at 50%, im not going to take any chances especially since the rotors are crazily expensive.
The ceramic rotors life is determined by weighing the rotor itself and not by measuring the thickness of the walls. The rotor is marked with the minimum weight that it needs to be before replacing them, if the rotors weight is under this specific weight it will need to be replaced. On this specific car it calls out “min. weight 4956 g”.
The rotors also have special marks that help with identifying in what condition they are, if the marks are smooth that means they are still in good condition, if the marks become rough that means they need to be replaced.
I've covered this in some posts in the past. A similar thing happened with my 2009 Jeep Wrangler Rubicon which I used to take off road a lot - now driven by my daughter while she's at college. The rear pads wore out very early while the front pads were almost new. Quite a head scratcher as this has never been the case before.
The problem is the traction control feature. While driving around in sandy washes in 2WD, the Jeep is frequently applying the rear brake to one wheel or the other to limit wheel spin. You don't really notice it, but it's wearing the heck out of the brakes if this gets engaged a lot.
Similarly on the E63s if you see the little yellow icon flash on the dash during spirited applications of throttle while in Comfort, Sport, or Sport+ mode this is the traction or stability control engaging to limit wheel spin. It will also engage in Race mode but is less aggressive and will let you hang the back out a bit before pulling it back in.
Every time the light comes on, that's some of your rear brake pads going poof.
In my 2018 I have the individual mode set to basically Race mode. Whenever I'm at one of my favorite corners or in some situation where I expect I might have a bit of wheel spin I flip the car to Individual mode. It's easier to have one flip up than three flips down and vice versa to get in/out of Race mode quickly.
You can turn TC all the way off, but this is obviously a use at your own risk don't try this on public roads, caveat, caveat, etc., move. At least one forum member did total their E63s on a public road when the car got unexpectedly out of shape under hard acceleration.
I did have a probable save once by traction control/stability control kicking in. Was doing some canyon carving up a local mountain road in Race mode when in mid corner with a bit of a drift going the car suddenly started to jump sideways. Pretty much before I could react the car cut the throttle and straightened itself out. I was like WTF just happened? Turns out I had cut the sidewall of the right rear tire on a rock I didn't see and the tire instantly deflated. I'd like to think I would have saved the car anyway, but no question that TC/SC helped me out a bunch.
Anyway, I think TC engaging is probably what's worn out your rear brakes sooner than expected.
In all my AMGs, the starting dance was brake, push stat button, push traction control into sport mode, push the button to switch trans, and accelerator into sport mode.
The W213 allowed me to set some of those into one button except the traction control so it was always a two-button dance every time I started the car. Maybe why my rear brakes weren't even half worn at 18k miles (running low 10s at 136mph on the draggy)
I did the rears on my wagon a couple years ago, and in a total brain fart I hit "pads fitted" on the dash without the calipers or pads installed on the rotors. The computer proceeded to push the pistons out of both calipers and dump all of the brake fluid all over the shop floor. I got an unexpected lesson on AMG rear caliper operation and assembly, and spent about 5 hours bleeding the system manually as I didn't have an ABS bleed tool / scanner. Not one of my finer wrenching moments
I actually jumped on here this evening wondering how to properly read the wear marks on the CCB rotors. I wasn't sure how the wear marks worked but now I know after looking at your graphics my fronts are still in good shape. 40k miles, multiple track days, rallies, hard driving with friends with supercars, etc. I'm really surprised the front pads still look ok. Probably will swap them out soon to be safe. I got a really bad screeching sound from the left front heading home, took it all apart and don't see anything obvious. Sounded like a rock between the rotor and back side dust shield or similar. Shield, rotor and pads look fine though so who knows. Hopefully it was an isolated incident as were taking the car on a road trip through the hills this weekend.
Am I the only person confused about this happening on a car with CCB's??? I understand the principle behind why this would happen with the rear brakes, but I'd never think at 13K miles. And I would NEVER think this is possible on CCB's. There must be a problem with the emergency brake or caliper not releasing the rear brakes or something. The seems way beyond normal to me. And I'd hate for the OP to have this same problem again, especially if it forces him to replace the rotors prematurely. OP, I didn;t see whre you mentioned anything about the lube/grease on the pins when you removed them, or when re installing.
Am I the only person confused about this happening on a car with CCB's??? I understand the principle behind why this would happen with the rear brakes, but I'd never think at 13K miles. And I would NEVER think this is possible on CCB's. There must be a problem with the emergency brake or caliper not releasing the rear brakes or something. The seems way beyond normal to me. And I'd hate for the OP to have this same problem again, especially if it forces him to replace the rotors prematurely. OP, I didn;t see whre you mentioned anything about the lube/grease on the pins when you removed them, or when re installing.
Otherwise, fantastic write up!
W213 traction control and ESP are based on the rear brakes engaging. Even the LSD is controlled by the rear brakes...add the "HOLD" feature and the rear brakes are used heavily.
The other thing that chews up the rear pads is the autonomous driving stuff on the freeway. I cannot believe that you only got 13K out of the factory pads though. I have the steel brakes on my 19 S63 and I have close to 30K on my powerstop ceramic pads all around and the rears still have about half the meat left. I always though that CCB brakes lasted a lot longer. Huh.
W213 traction control and ESP are based on the rear brakes engaging. Even the LSD is controlled by the rear brakes...add the "HOLD" feature and the rear brakes are used heavily.
I understand how the rear brakes are used for all the driving and stability systems. The only piece of good information the dealer gave me when I bought my S550 years back was about not using LKA for this very reason.
I now have an S63 so I know how the stuff works. 13K miles seems fast for steel brakes but ridiculous for CCB's. It's either sliding pins sticking, caliper piston malfunction, or bad brake proportioning valve. At 13K on CCB's, this doesn't seem like normal wear and tear, even with safety and stability systems.
Did you get a measurement of the pad thickness on both sides, all 4 pads? If there was any discrepancy then you have a sticking rear caliper which is usually indicative of sliding pins.
I have 146k miles on my OEM CCB rotors. The pads were replaced 10k miles ago and i have not had any issue with pad wear as of yet.
I'm also pretty sure that the TC is what worn out the rear brake pads, this car is one of the most stable cars i have ever driven, with over 600hp you can full throttle it and it wont never disappoint you with loss of traction.
I've covered this in some posts in the past. A similar thing happened with my 2009 Jeep Wrangler Rubicon which I used to take off road a lot - now driven by my daughter while she's at college. The rear pads wore out very early while the front pads were almost new. Quite a head scratcher as this has never been the case before.
The problem is the traction control feature. While driving around in sandy washes in 2WD, the Jeep is frequently applying the rear brake to one wheel or the other to limit wheel spin. You don't really notice it, but it's wearing the heck out of the brakes if this gets engaged a lot.
Similarly on the E63s if you see the little yellow icon flash on the dash during spirited applications of throttle while in Comfort, Sport, or Sport+ mode this is the traction or stability control engaging to limit wheel spin. It will also engage in Race mode but is less aggressive and will let you hang the back out a bit before pulling it back in.
Every time the light comes on, that's some of your rear brake pads going poof.
In my 2018 I have the individual mode set to basically Race mode. Whenever I'm at one of my favorite corners or in some situation where I expect I might have a bit of wheel spin I flip the car to Individual mode. It's easier to have one flip up than three flips down and vice versa to get in/out of Race mode quickly.
You can turn TC all the way off, but this is obviously a use at your own risk don't try this on public roads, caveat, caveat, etc., move. At least one forum member did total their E63s on a public road when the car got unexpectedly out of shape under hard acceleration.
I did have a probable save once by traction control/stability control kicking in. Was doing some canyon carving up a local mountain road in Race mode when in mid corner with a bit of a drift going the car suddenly started to jump sideways. Pretty much before I could react the car cut the throttle and straightened itself out. I was like WTF just happened? Turns out I had cut the sidewall of the right rear tire on a rock I didn't see and the tire instantly deflated. I'd like to think I would have saved the car anyway, but no question that TC/SC helped me out a bunch.
Anyway, I think TC engaging is probably what's worn out your rear brakes sooner than expected.
I'm also pretty sure that the TC is what worn out the rear brake pads, this car is one of the most stable cars i have ever driven, with over 600hp you can full throttle it and it wont never disappoint you with loss of traction.
you forgot one thing which is IMPORTANT for CCB equipped W213 and that is the wheel hanger tool.
I never used them, I'm extremely careful when removing/installing the wheels,
I am planning on buying them and i do recommend that everyone uses them and not take the risk of damaging the rotors, thanks
Am I the only person confused about this happening on a car with CCB's??? I understand the principle behind why this would happen with the rear brakes, but I'd never think at 13K miles. And I would NEVER think this is possible on CCB's. There must be a problem with the emergency brake or caliper not releasing the rear brakes or something. The seems way beyond normal to me. And I'd hate for the OP to have this same problem again, especially if it forces him to replace the rotors prematurely. OP, I didn;t see whre you mentioned anything about the lube/grease on the pins when you removed them, or when re installing.
Otherwise, fantastic write up!
at 13k miles i really didnt think i needed to lube the pins, i pulled one of the pins out and saw that the rubber accordion was full of grease so i didnt bother with the rest.
Did you get a measurement of the pad thickness on both sides, all 4 pads? If there was any discrepancy then you have a sticking rear caliper which is usually indicative of sliding pins.
I have 146k miles on my OEM CCB rotors. The pads were replaced 10k miles ago and i have not had any issue with pad wear as of yet.
Are you driving the car like a bat out of hell?
right side rear pads:
inner 4mm.
outer 3mm.
left side rear pad:
inner 5mm.
outer 5mm.
my explanation for the discrepancy is that the TC on the right side will work more than the left side due to the street conditions where the pavement on the right is usually more damaged than the left.
can you please check how much meat you have left on your rear brake pads @ 10k miles, how long did the previous ones last.
Great write up, definitely one I'll use in the future !
It is strange that they needed replacing so quickly, mine is on 38K and nowhere near need replacing. However the front discs started to delaminate, Mercedes contributed goodwill 80%, still not cheap, still not happy they failed but at least I didnt have to pay the whole amount. Front discs, pads should be good for a few more years!
