You don't need a special wrench...

http://v12uberalles.com/changing_oil_filter.htm

And yes, you'll need at least 10 quarts of oil.

Using the proper MB socket for that cap makes the job ten times easier. Plus you don't risk damaging that plastic cap. I don't mind buying tools.;)

Im going to try to do this on thursday. I cant believe you got to take out the whole air box, and even the rivet on the aux fan. Man this seems crazy. Hopefully its pretty easy.

120 oil change.
 

Just remove the air box, 2 or 3- 10mm bolts. Be careful of the air mass sensor. The filter cap is right in view. BTW. It takes exactly 12 quarts of Mobile 1......pricy oil change!.I use an oil filter wrench that fit my old BMW 2002. works great.May want to check the thermostat, mine was bad and causing slow warm up.

I checked that site that you guys linked about how to do it yourself stuff
(thanks for that link) it seems kind of complicated for the first time since I never had to do it that way, and I always been scared of working on things with so little room and so many things I never seen ( im use to working on older cars) that everything is so easy to get to.

I think Im going to try to do this on thursday. It looks like theres 2 air filters on this right? one on the left and one on the right? I called this local shop that works on mercedes and he wanted $180.00 to change the oil. I about laughed when he said that especially when the dealership is only charging me 85 bucks to do an oil change. I couldnt believe it. But I want to start learning how to do things on this car myself. So later this week I will let you know what happend.

Yes, there are two air filters, one on each side.

You can do this oil change. It's a simple job, but it's tedious because of the amount of stuff you have to remove to access the filter. Just remember to have a catch pan big enough to hold all that old oil...otherwise you'll have a mini Exxon Valdez in your garage.

Well consider that 12 quarts of Mobil 1 0w40 costs what, $5.50 on sale each, so $66 for oil, and another what $15 for the filter. $81 in parts alone, add in a half hour of a techs labor at $100 an hour. I come up with about $121ish.

Looks like the big job ( not really but just wanted to say that) tomorrow.
Im got to go buy the 15 qt drain pan, and the oil. I will let you know how it went later tomorrow.