20K mile B service update
 

20K mile, B service on my 2018 450 4Matic
1. front brake pads at 3mm, rear at 4mm. Wow- so much pad wear.
2. coolant cap replaced due to seal issue as i was getting a message 'coolant low....'. known problem apparently as it was replaced with a redesigned version of the cap.
3. centre console armrest was not heating with the seats and door armrests. burnt out so will be replaced.
4. rear headrest rattle - removed and lubed.
5. whining noise from rear drivetrain - could not be reproduced apparently. Will have to drive along with tech to demonstrate it.

is the brake pad wear normal?

If you use distronic a lot, yes this wears out the pads.
Stability control also uses the pads to stabilize the car.

The only part of distronic I don't like is when you approach stopped traffic at speed the system waits too long and then brakes heavily. I tend to work around this by overriding it and braking more gently.

27K for mine and the pads were done- front and rear. They work very well but I will be switching to the ceramic Disc Italia pads for a lower dust and longer life on the next brake job. The dust is insane, constantly cleaning the rims.

good to know. thanks. Does anyone know if brakes are included in the prepaid maintenance?

Agree with this one
 

You are so correct. Almost feels like I am speeding up, just prior to Distronic engaging braking for stop lights. I initiate manual braking anytime I see traffic stopped at a light.

I believe so, I just extended mine and the filters and oil change and wipers were included.

I had the Disc Italia pads installed soon after I bought the car. After one year (8K miles) the pads were at 11 MM. The wheels stay a lot cleaner as well.

Item #5 I have a whining noise I can replicate. At approximately 56MPH to 63MPH the whine will occur. It does not matter what gear the car in in and will change with speed. I was told this was normal. I have yet to check in another car.

ive never heard it in my car.

If it changes with the speed and gear doesn't matter, even neutral, it would point to the rear differential. A whining is usually indicative of the diff. Hubs make some strange noise when bad also which is a possibility if speed related but not gear. Old or worn tires can roar and make road noise but not whine. If it's not rpm based that eliminates the engine, if not gear based or sure it's not trans the next is the diff and hubs. They can put a device in your car to determine it's location. If I remember its a picoscope. The dealer will have one.

Found it:https://www.picoauto.com/products/no...g/nvh-overview

Unless you get a really good AND S class experienced dealer you will get the run around until you give them a TSB. I got mine cleared up when I gave them a copy with my work order.
They often say o yeah that doesn't apply blah blah. There are other tech tips/news sent or available to dealer techs that are not published as a full on TSB. Not aware how to get them.
There are probably other TSB's on this issue.

LI35.31-P-061268 APR15 – 222 up to production date 10/10/14 rear axle drive train howling noise between 50 & 70 mph, check left side shaft to see if rotary mass has been installed on inner joint.

LI35.00-P-060851 FEB15 – 222 4matic produced before 10/14 howling or whistling from rear differential @ 50-60 mph, replace rear axle shaft to part 2223507802 (has updated damper).

In Canada besides the normal wty there is a wear warranty for 2 years/40 K that includes brakes pads/rotors.
Makes sense when the car is applying the brakes on it's own in many situations. (When it's raining being a weird one)

I completely agree and do the same thing. The system is magnificent, but good drivers will always monitor it.

ANY downside to the ceramic pads? Squeaks? Noise? What does MB say about it? Any problems voiding some warranty aspects?

i did give them print outs of the two TSBs when I dropped the car off. didn't help I guess. i have to go back and help them identify the noise.

I will print this out and bring it with my next service. Thanks for the information.

They are more expensive than most brake pads. I know MB will not install them so I had an independent shop do the work. I can't see how they would void warranty but I feel it's low risk.

But no squeaks, noises and much less dust?

[QUOTE=Streamliner;7695874]But no squeaks, noises and much less dust?[/QUO
They work great! Perform as well or better than the OEM parts. There is still some dust but much lighter color and less of it so does not show for quite a while. No squeaks or any kind of noise. The only downside I am aware of is cold weather performance. They don't stop as well until they warm up.

3. centre console armrest was not heating with the seats and door armrests. burnt out so will be replaced.
The part was ordered from Germany- took three days. Centre Console has to be removed to install this part - took a day plus to install the part..hopefully pick up the car tomorrow.

Ceramic pads
 

my mechanic told me ceramic pads will wear out the rotors faster as they are a harder material.

I have never found that to be true with ceramics in comparison to the stock pads. The stock pads are almost a racing compound made by Brembo and Pagid. Very aggressive to the rotors. Mercedes designs it for cold and hot stopping all climates, and to compromise the rotor by design. Go to Mercedes for a brake job and it includes rotors as they don't cut them. I find 2-3 sets of pads (Mercedes pads) on a set of rotors...if you catch it before the sensors go off. When changing brands or material I think the biggest question is will it be aggressive enough as it's a heavy car. It seems the Disc Italia have found a sweet spot it having great stopping power and low dust which indicate its a little less aggressive with still being effective. This will be my last set of MB pads going to try the Disc Italia after much research and reviews from members.Tired of the dust....

That whine you described was identical to mine and they are replacing the rear diff tomorrow.

I always laugh when I see people will give up stopping power to avoid brake dust. I get the idea as who likes dirty rims but brake pads have a lot to do with your stopping power which you are finding out with cold weather performance. Some rotor co's don't like certain low dust pads as they aren't as aggressive as other pads. This can lead to uneven deposits and shakes.

I have no problem trying more aggressive pads on older or performance cars but any mechanic will tell you they would rather just use the OEM right from the dealer as it eliminates so many issues. I would try a wheel coating vs low dust pads.

Mercedes pads wear the rotors as they see the rotors as wear items and they work with the pad compound vs a pad that doesn't. Your new pad will not clean off pad deposits and can lead to what people think are warped rotors. After long research???? Ok, what is the stopping distance difference? Kid jumps out in front 5' is a huge difference. I would go even more aggressive but never give up for dust.