Hey all. I’ve been strolling around this forum and decided to join today. I’ve been researching on here through Google search, about the pros and cons, and common issues with the w222 with the m278 engine. So far I have gathered knowledge about these specific issues with the w222 platform:

- Coolant hoses tend to fail prematurely (plastic deteriorating)
- Camshaft magnets leak oil (can be bad if disregarded and destroy the alternator)
- Timing cover may leak oil
- V8 engines like to go through motor mounts
- Camshaft sprockets could possible destroy themselves(?)

I’m not 100% sure on the last one as I learned about it on YouTube where a person had that issue but on his 221 with a m278. Is there anything else about these cars that should be known before purchasing? I owned German cars about 20 years ago (E46 325i & 330Ci), loved them, and understand the engineering behind German built luxury and the costs associated with them. I am a DIY’er with about 24 years of experience working on cars of all makes.

All of the issues I listed, to me, seems like the owners either didn’t know the problems were beginning to occur, or simply just didn’t care to have repaired and a domino-effect of issues piled up.

I’m looking for 2018-2020 S560’s since CarPlay was updated in those years. I appreciate any advice. =)

Edit: Meant to say m176 not m278

My advice to you is to look at all the cars on sale in the US and read ALL the Carfax reports. Make a chart of mileage, maintenance, and repairs. That's a much better indicator of potential problems you might encounter. Also, you mentioned M278 engines, but 2018-2020 don't use that engine.

I have been doing just that, so I appreciate the response. I’m assuming that the m278’s successor then is the m176?

279 powered cars suffer none of the ills you describe above.

Yes, you got it right. When they went from the S550 to the S560 they replaced the M278 4.7 liter TT V8 with the 4.0TT motor, M176. Your list of problems is interesting:

- Coolant hoses tend to fail prematurely (plastic deteriorating)
Tell us more about what you've found with premature coolant hose failure. How frequently did you see it in your research?
- Camshaft magnets leak oil (can be bad if disregarded and destroy the alternator)
How often did you see this happen, or was it from some YouTuber with a "better watch out for COMMON problems" video? My personal opinion...they're just there for clickbait. Afterall, that's what YouTube is all about now. I don't say that to sound negative, I work in Advertising and buy ad time and create content for YouTube, FYI. That problem was on the M278, but I don't remember it being a frequent problem
- Timing cover may leak oil
I've seen this happen only once on an M176 motor and the guy is here on the forum. I've personally scoured 250+ S560 Carfax reports and never saw another one. This happens more with the M177 motors in the AMG cars than in the non-AMG cars.
- V8 engines like to go through motor mounts
This is another anecdotal claim made by YouTubers, at least as far as I can see. What does "common" mean anyway? Is it "when" they see a problem or does it happen 100 times per year, or in 5 years???
- Camshaft sprockets could possible destroy themselves(?)
Not sure I've come across this before, either from research or even claims from Youtube on the M176 engine. Tell us more...

Please don't listen to the YouTube review guys; they don't know anything about these cars. Their goal is to get likes and subs and increase SEO if they have an auto shop, not to properly inform anybody. If they did, they would state the number of cars they've personally worked on or provide some real numbers about how frequently a problem occurs. I don't dislike the people who do it, just the niusinformation that is spread. If you go back to the M278 engine, there are problems that are common to those, but the oil wicking problem which seems to be the most prevalent, can be solved for minimal effort and cost.

We have seen two instances of M176 valve cover leaks on this board. Which would not be a big deal in my book if the repair wasn't such an labor intensive process ($$$ at the dealer)

I'd only heard about the one, but definitely trust what you're saying. Expensive repairs suck!! However, that doesn't mean they happen often enough for concern. And there are some things you can do to reduce your chances of that happening. I know one of the guys who suffered the valve cover leak is a Real Estate agent. One of the worst things for any car, especially cars with tight tolerances is frequent stops and starts. My "assumption" or "theory of the case" is that as he was frequently taking short trips, possibly when driving from home to home, either with clients in his car or otherwise; the frequency of short duration use possibly contributed to the premature failure of his valve cover gaskets/seals. Just a hypothesis, but one solid use case to be considered.

They’re awesome cars, happy hunting, and go for the most your budget allows.

Hope you find a nice car and enjoy it.

I think the failing 'plastic hoses' refers to the turbo coolant lines which oddly enough, do have plastic sections.

Some of the items you’ve mentioned are normal wear items for Mercedes.

We’ve had to reseal the timing covers and replace the motor and transmission mounts on the wife’s W212.

Both occurred north of 100k miles, and wouldn’t put me off from purchasing a W222.

It is a bit of ‘gotta pay to play’, but with a car this good, it’s definitely worthwhile (in my opinion).

I have been pleasantly surprised at how little I have needed to do with my ‘15 S65.

A water pump and idlers. A pulsation dampener for MBC. Sunroof rails. Fluids. Tires. Front suspension upper and lower arms (once!). Spark plugs. One ignition coil. Brake pads once in 140,000 miles. Windshields (rolls eyes). This car is soooo much better than the 221 S65!

I believe if Mercedes-Benz would attempt to make the most trouble free car in the world they could do it in a heartbeat . Some say to stay away from twin turbo V8 M278 engines as well. Honestly, it's worth all the trouble and it's durable engine to me . I have seen many of them having more than 150K miles and still running strong . Those cars are heavy too and considering their weight their suspension components are tough shell too

Hey, speaking of the sacrificial wires for the M278 cam sensors and solenoids, I have a set I bought for my 2016 that I'm told aren't need on my new M176. And, come to think of it, a couple of extra spark plug boots ... Glad to pass on to someone who wants them ... send a PM if interested...

Hi Tom, I bought a ‘16 S550 couple months ago. I would be interested. My email ricgold@gmail.com
Thank you

Just a beautiful dinasour of efficiency and restraint lol

I'm looking to get back into the W222. My 2018 was a s450. I'm looking at a 2020 S560 with 20K miles on it. Any cautions?

Get a pre-purchase inspection.

Why did you get rid of the S450 and what is driving you to an S560 vs another S450?

Is that to say the M279 V12 is a more reliable engine than the V8, or are you just joking around that it doesn't have *those* specific issues?

Would be amazing to hear the V12 is the most reliable engine in the group

My 2015 W222 V12 (S-600) has not given me any grief--but the maintenance is necessarily higher than the V8 or V6 (or I6).

The only issues I have had are::
a) I hit a deer--or more precisely, the deer ran in front of my car.
b) the coolant tube through the windshield washer fluid container started a slow leak.
c) main battery life is 5-odd years.

I hope to keep this car as long as I am driving.

142,000 miles on mine. The Bent-12 has needed a water pump, serp belt, tensioner and idlers, one ignition coil and spark plugs. Two dozen at a time. Never an oil leak. No drama. Still shoves me back in the seat with all 740lb/ft when asked. Uses a quart of mile during an oil change interval.

The V12 dates back several decades now so it's definitely the most fined tuned, it's also simpler and less stressed.
So likely the most reliable although not the most affordable to maintain.

I fully agree!…If I wanted power and performance, I’d rather be in a car with the V12 instead of a tuned V8 AMG engine…. The V12 wins in terms of reliability, fun aspect, performance and exclusivity. Maintenance cost difference shouldn’t be a factor when you step into any of these tow variants (they are a bad financial decision regardless, so I’d rather get the V12 anyway).

I always wanted an M760, but I have very specific colors and options as a must-have and am sure there is only a few in the US built just like I want it - very slim chance to find the one Before they get too old to buy soon so I think I passed on the idea already more than a year ago. The right time to buy one was brand-new in 2020 when they were built with all options available before they canceled packages for the 2021 and 2022 final year.

The 560 feels much better than the 450.

Especially with the RENNtech tune.