When the harmonic balancer failed on my co-workers 1998 C280, it failed on the freeway, and did considerable damage to the engine.
The engine had to be removed from the car and completely rebuilt.
The car was out of warranty so she took it in the shorts.
Just thought I'd warn you that more harm can be done than just to the timing cover and oil pan.
2001 E430, Bourdeaux Red, Oyster interior.
1973 280SE 4.5, 170,000 miles. 568 Signal Red, Black MB Tex. "The Red Baron".