This TSB applies to 2008 Mercedes-Benz C300 vehicles and other models equipped with the 272 or 273 engine. According to Mercedes-Benz, in isolated cases, engine oil loss can occur at any of the three rear camshaft cover caps.
The cause is attributed to leaking at the cap sealing ring(s), in the event of borderline tolerances and under unfavorable climatic conditions, when the sealing ring can lose its preload.
If the rear cam caps are leaking, replace the caps.
Small diameter cap……….P/N A000 998 55 90….Quantity 2
Large diameter cap……….P/N A000 998 56 90….Quantity 1