Zeus, Sorry to hear of your problem with the high oil consumption, and the gauntlet you are experiencing. The problem seems to stem from the the wrong type of oil (Dino), used at those 10000 mile extended intervals.

Since having changed to synthetic oils, and if you wish to continue using them, I would go to Mobil 1 Delvac in a 5W-40 weight, for it's cleaning effect. It is very high in detergents and anti-corrosive additives, to meet the Heavy Duty Diesel Req'ts. for that purpose. It can be also used in spark ignition engines-gasoline, as it is formulated for that use also. I would try this before tearing into the engine or selling it.

I would use the Dino version of Mobil Delvac 15W-40 $8-9./gal., and add Marvel Mystery Oil to the engine oil and to the fuel. Buy a 1 gal. jug of MMO, at Wmart for about $12.50, and use it as directed for mixing with the oil and fuel. It will turn the oil black pretty quick, and you may want to change it at 1000-2000 mile intervals, with a new oil filter. Add the Dino 15W-40, as needed for topping up. Do this several times before you give up on it. MMO is used in the USAF by 55gal. drums in older non-turbine engines. Gen. Aviaton too.

If all this doesn't solve the problem, I would use Dino HDEO's like Mobil Delvac Super 1300 or Shell Rotella, Chevron DELO, etc., and keep the oil consumption to more reasonable levels. Oil consumption or use is not bad for an engine, it's bad for emissions and the wallet. Don't tear the engine down, if you can reduce the oil consumption, by whatever means you can find that will help reduce or stop it. Good Luck.

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SONNY was right...Nobody Cares.
Calogero, from the movie, "A BRONX TALE."

I will agree with this, and with Hatteras. I will also add that 30-weight is simply too thin for a V8 like this. I will ALSO agree that yes, you do need to drive these cars hard and not necessarily baby them. Different motor, but my m111 burns ZERO oil at a 5k change interval, 229.51 dealer 5w40, previously 15w50 M1 (unnecessarily thick, so I changed). I have beat the crap out of this motor for 105k, and it has 165k on the clock.


THAT SAID......simply put, run the Delvac 5w40 (or M1 HD truck and SUV is what they call it now), then after 2k or so use the M1 15w50 SuperSyn and see what happens to your consumption

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former: 83 300D, 97 C230, 93 400E

current: 08 C300 Luxury , 92 500SL

I spoke with the Service Manager at the Mercedes dealer here. He was polite and listened, and apparently hadn't heard of sludging issues on the M112/113 nor the O'Keefe lawsuit in the US. He agreed it wouldn't hurt to approach MB Canada and see if they'll do anything to help. First step is an initial inspection at the dealer, I'm booked for an appt in about a week and a half. Then take it from there.

Thanks for all the replies and I really appreciate all the help.

I've been doing plenty of reading and research about sludge and it seems like there are plenty of examples of cars (especially post 1998) having this problem. Not just Mercedes but also BMW, Lexus, Toyota, Audi, VW, etc. Most seem to be related to a combination of city driving and extended oil change intervals.

I agree with you guys on the trying to clean it option. If I don't get any help from MB (and I'm not holding my breath there), I may as well try and clean the engine up using an appropriate oil or in conjunction with a cleaner instead of simply getting another engine right away. Nothing to lose in trying. If I can get consumption low enough, I'll be happy with that.

Drove the car today and it runs so perfectly, you'd swear there is nothing wrong. Watched the exhaust when I started it, especially in the morning, and there was nothing - no smoke at all. Same while driving. Bizarre. Unless my cats are sucking it all up...

So, who knows...we'll see how it pans out (no pun intended).

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Chris
2007 E550 4Matic - 61,000 Km - Iridium Silver, black leather, Sport package, Premium 2 package
2007 GL450 4Matic - 62,000 Km - Obsidian Black Metallic, black leather, all options
1998 E430 - sold
1989 300E - 333,000 Km - sold
1977 280E - sold
1971 250 - retired

"And a frign hat. They gave me a hat at the annual benefits meeting. I said. how does this benefit me. I dont have anything from the company.. So they gave me a hat." - TheDon