Mercedes-Benz 2004 C-Class Coupe Operator's Manual page 240

Operation
Engine compartment
C 230 Kompressor
1 Oil filler cap
Unscrew oil filler cap 1 from filler
neck.
Add engine oil as required. Be careful
not to overfill with oil.
Be careful not to spill any oil when adding.
Avoid environmental damage caused by oil
entering the ground or water.
240
!
Excess oil must be siphoned or drained
off. It could cause damage to the
engine and catalytic converter not
covered by the Mercedes-Benz Limited
Warranty.
Screw oil filler cap 1 back on filler
neck.
C 320
1 Oil filler cap
Unscrew oil filler cap 1 from filler
neck.
Add engine oil as required. Be careful
not to overfill with oil.
Be careful not to spill any oil when adding.
Avoid environmental damage caused by oil
entering the ground or water.
!
Excess oil must be siphoned or drained
off. It could cause damage to the
engine and catalytic converter not
covered by the Mercedes-Benz Limited
Warranty.
Screw oil filler cap 1 back on filler
neck.
For more information on engine oil, see
"Technical data" section ( page 330).