Hellow,

What is a normal oil consumption for a c55? I had to fill it up with 1l oil every 5000km. Normal use, no trackday use. Oil 0W30 Mercedes

I drove it today and when i accelerate in 3th gear till limiter, i saw some blue smoke in the rear window. I don't have this smoke often, or i don't notice it everytime.

Worrying?

 

I believe AMG put out a service advisory stating that 1qt/1000mi (roughly 1 ltr/1600km) is considered normal.

I've had 2 C55s and they both burned more oil than that - 1qt/300mi on my first one and 1qt/400mi on my current car. Other people report almost no oil consumption. Luck of the draw I guess.

Mine blows blue smoke when at full throttle too, but only after driving around 100 miles at a steady pace. I was beginning to suspect worn rings on my previous car before it was wrecked. I haven't done any diagnosis on my current one as of yet. I plan to drive it until I can no longer register it or it stops running.

Just carry a couple of quarts with you...

 

Hi, ok thx for the info.

Do you use 0w30 oil?

 

If that is all I can find - I try to run slightly thicker but still approved oil. 0w-40 to 5w-40, especially in the summer months.

 

I read somewhere on Mercedes Bevo that 0W-40 / 5W-40 are to be used with AMGs. 0W-30 is too thin for your AMG.

 

Hmm, weird because i go to official AMG/Mercedes dealership and they use 0w30 on both my c55 amg.

thx for this info

 

The last 12 years I used Mobil 1 5-50 in my C55, and I have "normal" oil consumption.
Heard that the M 113 EVO engine is the last MB engine you can use the "5-50" in.

 

My C55 has 0 oil leaks and burns 1 quart every 1k miles. 0W40 Mobil 1.

 

After doing much research, it appears the M113/M112 isn't as bulletproof as most people think.

The oil rings can become "stuck," from neglected oil changes, using mineral oil instead of synthetic, or just bad luck. It is a design flaw brought about from gas mileage regulations and the need for thinner oil to reduce drag (or so I have surmised). The oil rings are thinner than usual and tend to warp/bend in the piston ring lands. (For those who don't know, most pistons have 2 solid compression rings on top and a third oil seal ring below that, which isn't solid, but kinda looks like corrugated cardboard). Eventually, the bent/stuck oil rings will start to score the cylinder wall and destroy the block (since the cylinders have a special coating and cannot be honed or bored out). This in turn will cause the car to start burning oil like there's no tomorrow. Still plenty of compression and normal gas mileage, but a serious drinking problem. This is a common problem with engines from quite a few manufacturers including Volkswagen/Audi (2.0T) and others (apparently including Mercedes) in the early 2000's through the mid to late 2010's.

It is critical that you keep the oil clean and run the recommended thin (0-30 to 5-40) synthetic oil and nothing else. Thicker oil (or non-synthetic) will result in stuck oil rings and make things worse, not better.

Apparently, the 10k factory intervals are probably too long as well. I have been changing oil right at the recommended 10k, using approved oil, and adding in between changes to keep it full. Not good enough. It's getting worse. Up to 1 quart every 200 miles.

Looks like I need to borescope the cylinders and if they aren't scored, pull the pistons and replace the oil rings. Otherwise, I'll need a new engine sometime soon which hopefully doesn't have the same problem (I'm 2/2 so far though). If I have to go to the expense of sleeving the block, I will also be changing out the factory pistons to ones with a thicker oil ring. Of course at this point, I will be doing this with an M113K...

My next step before doing anything drastic I will be trying a combination of Amsoil Performance Improver to clean the top side of the piston rings through the injectors and Engine and Transmission flush to clean underneath with the oil to see if I can chemically save the engine. I'll post the results when I know them.

 

I think this depends on climate and oil you use. I always use 0w40 but I swear sometimes the car is fine between oil changes while other times it'll flash a low oil lamp. My driving habits are more or less the same.

 

 

Hello Spooky55,

Do have any results or found the problem? I’m very curious because I’m starting to have the same problems with slow increases of oil consumption.