I'm sure I'll get flamed for this, but Mercedes isn't without fault. Let's not forget the cracked 14 heads on the 603's and the oil control and rod bending issues of the later 3.5L 603. Even with those issues, they seem to be pretty tank-like engines.

The 603 in my SDL is original to the car, and despite looking gunky on the outside and having clogged manifolds, the inside of it still looked nearly factory fresh after 30 years of abuse and neglect.

__________________
Current stable:
1995 E320 157K (Nancy)
1983 500SL 125K (SLoL)

Gone but not forgotten:
1986 300SDL (RIP)
1991 350SD
1991 560SEL
1990 560SEL
1986 500SEL Euro (Rusted to nothing at 47K!)

Gone and wanting to forget:
1985 524TD 167K (TotalDumpster™) [Definitely NOT a Benz]