Simply stated, all Mercedes Dealerships use oil extractors seeing as how the engines are designed specifically for the extraction of oil through the dipstick tube. PERIOD.
MB has been vacuuming for years. Works great, leaves possibly less than draining as the drain plug has threads that recess up into the pan! No matter which way you tilt the car, you'll never get all the oil out of the pan unless you drop it. And no dealer is going to mandate dropping the pan on every oil change. Extraction is the best way to go.
Here's the TSB stating the approved equipment for use by dealers' service dept...
Date: March 2001
Order No.: S-SI-58.00/118
Supersedes:
Group 58
SUBJECT:
ALL ENGINES
APPROVED OIL EVACUATION EQUIPMENT
The purpose of this Service Information is to inform dealers that Approved Oil Evacuation Equipment, which is used to extract used engine oil from the engine via the oil dipstick tube, is now available for order. Mercedes-Benz engines are designed to allow the extraction of engine oil from under the hood via the dipstick tube. The engine dipstick tube has an enlarged cross section, plus a formed extension at the top end where the dipstick is inserted and the approved engine oil evacuation equipment interfaces. The opposite end of the dipstick ends just short of the oil pan bottom, thus engine oil can be extracted via the approved oil evacuation equipment by using the dipstick tube. Additionally, the engine dipstick tube itself is the conduit through which spent engine oil is moved to the oil evacuation equipment.
In addition, service and repair components for existing approved oil evacuation equipment is also available.
Note: Because the engine oil dipstick tube is the conduit through which spent engine oil is extracted, inserting tubular probes through the dipstick tube is NOT recommended.
Special Note for M-class:
Due to the location of the vehicle frame and suspension components, the draining of engine oil via the engine crankcase oil drain plug is not recommended, since this can lead to engine oil coming in contact and subsequently be damaging to the rubber suspension components. Thus, it is strongly recommended to use the approved oil evacuation equipment contained in the Service Information for this purpose.
Index
1. FLACO
2. RAASM
3. BDM Engineering
4. Deutsche Tecalemit (DT)
WARNING! This approved oil evacuation equipment is to be exclusively used for the evacuation of engine oil, transmission oil, power steering oil, and differential oil only.
^ Do not use this equipment to extract caustic (i.e. battery acid) or flammable liquids (i.e. gasolines).
^ Do not expose the waste oil reservoir to any source of heat.
^ Do not perform any welding repairs on the oil evacuation equipment.
^ Wear face and hand protection when extracting engine oil of high temperature.
^ Use the oil evacuation equipment only for the extraction of oil.
^ Do not modify any of the equipment component.
I use a Mityvac to extract 8.5 qts every time. Drain the oil from underneath via the drain plug and measure how much you get. My bet is that I'll extract more up top every time.