Ignore Mercedes Maint. System indicator for oil changes?
 

Car is an 06 C350, production 6-05. It has had 3 oil changes since new, last one (according to documentation) was at 20k; has 25k now and the indicator says the oil has 8500 miles to go.

I just can't stomach a 13k oil change interval, can you?

My hunch is to change it now, at 5k, as I have always done with my previous Benzes. What's the skinny on the oil computer and the 229.51 5w40 over 13k miles?

I change the oil and filter twice between service intervals. I'm like you, I can't stomach going 12 to 13.5k miles between oil and filter changes. I only drive about 5,000 mile per year so I don't like going through 2 summers on the same oil. I use Mobil 1 and MB oil filters.

Why not go 10k and have it tested then decide if it is ok to go 13k based on the analysis? The computer will track your driving style and adjust the interval if/as needed.

Engines get cleaner, filters get better and syn oil is higher quality every day.

SLK - My 99's manual tells me to follow the FSS OR change it every year, whichever comes sooner.

You can use the 229.51 synthetic if you want to, but 229.5 is all you really need. The 229.51 is the recommended oil for the OM642 V-6 diesel engine. The 229.51 is needed to protect the diesel particulate filter from clogging up.

Hey, now's your chance to learn something about motor oils of the 21st century to supplement your current '57 chevy knowledge.

http://www.benzworld.org/forums/w211-e-class/1304532-oil-change-siphoning-w211-3.html#post2246550

I'm no expert, but 13k on synthetic is probably ok. I used to go 10k on my 1990 Ford van no problem.

My 99 ML was the first MB I've owned that followed the FSS oil change intervals. I had no adverse effects doing so and I traded it in at 100K.

My 07 ML has the same type of interval. I'm pretty confident that synthetic can do its job at those mileage numbers.

The other two MBs are on dino and get a far more frequent oil change routine...

My w124 and my VW before that had what I thought (at the time) to be outrageous oil change intervals - 7500 miles. But with a service coming every 15K (minor, major, minor etc.) it kind of made sense. Don't shoot the messenger here, but if I'm not mistaken they also said you could change the oil filter every [I]other[I] oil change... FWIW I try to remember to change every 5K (but don't feel guilty if I go further) because its easy for my addled brain to remember. And nothing but dyno oil here.

Yes, I know, but I like overkill when it comes to oil :D

Ever since running Delvac 1 in my old diesels, I know how well that stuff can scour a diesel motor; imagine how clean it can keep a gasser

lol, that's cute, but I'm barely old enough to have grown up with the 76 Eldorado. My first car (87 Jetta) was fed a steady diet of Mobil 1, suffice to say I've never even purchased dino oil in my life! 5k miles on synthetic was a bonus over 3k on dino, circa 1990.

That said, you're all probably right (though I've got SLK's back), and I will run it til the computer yells. Modern MBs aren't meant to be kept anyway; unless maybe it's a CL63 that you drive 2k/year

I don't see why once a year or 13k miles would be out of the question.

I would certianly send a sample off to the lab to confirm what the computer is saying though.:D If the lab says 13k miles is ok than its ok. Modern engines don't really put a lot of crap into the oil.

You can run Delvac 1 in the old 606/603 diesels for 8k-10k miles without a problem, so you should be able to go longer with the new ones.

Its got a time counter as well and will have you change it after about a year if the mileage requirement isn't met.

Well, for 75% of cars on FSS systems the oil change interval of 12K miles will work out just fine. BUT for the rest of those cars following that schedule leads to SLUDGE.

Have seen cars with "perfect FSS" service history & an engine that was so sludged that you wouldn't want it. SOME need complete disassembly.

If you drive in a metro area FSS doesn't suggest for oil changes soon enough.

I thought FSS and MMS were different; the 05-up MMS supposedly being better at scheduling; I also thought the 98-04 sludge issues were due to using DINO oil on FSS cars......
:confused:

No, the 2005 & later cars have even extended oil changes....some as much as 16K miles.

Sludge happens even with synthetic oil!
MB started using ONLY synthetics in 2001! The early FSS cars that used dino oils were from 1998-mid 2000.


MBUSA has also warned that use of 229.51 oils in gasoline powered engines is NO longer recommended!