I have a 2004 CLK320 with the 722.618 transmission. I have asked two dealers here, and I've emailed Mobil 1. Nobody has given me a definitive answer. Can anyone tell me whether or not this fluid will work with this transmission? If you read the spec on the bottle, it says it meets 236.1 (among many others). That should do it shouldn't it? Any clarity here would be appreciated. What I want to do is pull as much fluid from the trans as possible and replenish. Drive the car a bit, and repeat. Do that a few times and I should get a fairly clean oil change without having to have it flushed by a machine. I just had the filter replaced...now it's time to get as fresh of oil as possible. I am NOT paying $17 a litre from Mercedes. I was born at night...but not last night. Shoot...one of the dealers here charges that for BG fluid! Thanks guys.
236.1 DOES NOT MEET SPEC.
Minimum spec is 236.10, which comes after 236.9 and is not the same as 236.1 (which is before 236.3, 236.2, etc.). So you can use spec numbers equalling or higher than 236.10, but not lower.
There are other fluids out there, but NOT MOBIL1 or any flavor of Dexron.
Loubapache posted a pretty comprehensive list in the 210 forum of fluids that meet minimum spec, same transmission.
FWIW, you do need to drop the pan and clean it and change the filter. Flushing won't get rid of all the detritus that has accumulated there.
There is also a self-flushing technique you can use that is in the 210 stickies.
However, fluid as you note is expensive (shop around, different dealers charge different prices). So if you flush you have to buy LOTS more. 4L will be more than enough for a pan drop and filter change, then in 10,000 miles you can just drain and refill, which will get you to the 60% range or so. You can also submit some of the fluid at the 10K change to Blackstone and they will tell you the approximate wear characteristics and longevity.