Date registered: Sep 2006
Vehicle: 2004 CLK 240 Coupe
Location: Norfolk. UK
Mentioned: 11 Post(s)
Quoted: 385 Post(s)
As I understand it, the old Service A & B were discontinued for your W211 class, and replaced by listed 'services' 1 to 20 to cover the entire vehicle. (ASSYST)
These specify items that need checking or replacement according to distance or time. Most are listed as every 2 years.
Engine oil & filter replacement is covered by another schedule that depends on the oil used, eg MB spec 229.5 is OK for up to 20k km.