Here's a link to help you out: http://www.benzworld.org/forums/w210-e-class/1279811-diy-oil-change-e420.html They cover both draining from under the car and sucking it out the dip stick.
it is located in the trunk of the car
It is under the back seat on the passenger side.....
Underneath the air filter box. You have to remove the air filter box first then you will see a cylindrical shaped can sticking out from the top right portion of the motor. Remove the top screw and you will find your oil filter in there. It is just the guts for the filter that get replaced. Go buy the filter first and you will see what I mean.
Usually next to the fuel pump, back near the tank.
420
The 1990 Mercedes 420 SEL does not have a cabin air filter in the way modern vehicles do. Instead, it uses a simple ventilation system without a dedicated filter for the cabin air. However, some owners may choose to install aftermarket solutions to improve air quality inside the vehicle. Regular maintenance of the ventilation system is still important for optimal performance.
look at the front of the engine on the passenger side , at the bottom you will see a aluminum canister with a bolt going through the cap of it . remove that bolt and the cap will come right off , and inside you will find the oil filter .
420 does i really hope.
blaupunct
The 1986 Mercedes 420 SEL typically holds about 8 quarts (approximately 7.6 liters) of engine oil, including the oil filter. It's important to check the owner's manual for the specific model, as oil capacity can vary slightly depending on the configuration and whether the oil filter is changed. Always ensure to use the recommended oil type for optimal performance.
Torque specs for WATER PUMP Mercedes 420 SEL are: 7.3 diesel and 15 to 18 foot pounds of torque
where is the fuse location for a 1995 Mercedes s 420