M156 vs OM606
Side-by-side reliability comparison
Higher reliability score
OM606
BEST
96/100
+36 points over M156
0
/ 100
CAUTION
M156
Mercedes-Benz
0
/ 100
BEST
OM606
Mercedes-Benz
Specifications
M156
OM606
Brand
Mercedes-Benz
Mercedes-Benz
Verdict
CAUTION
BEST
Reliability
60
96
Years
2006--2015
1993--2001
Displacement
6208 cc
2996 cc
Layout
V8
I6
Type
Petrol Na
Diesel
Power
457--514 hp
134--174 hp
Known Issues
2
2
Total Risk Cost
€2,500--€7,500
€280--€700
Character
M156
"C63/E63/S63 W204/W212/W221. Head bolt failure on early units (2007-2008). Intake manifold swirl flap. Cam adjuster bolts. Incredible NA V8 sound. Later production much improved."
OM606
"Legendary. 500k+ miles documented. Tunable to 500hp. One of most reliable engines ever."
Issues Comparison
M156 2
◆ CRITICAL
Head bolt failure (2007-2008)
▲ HIGH
Intake manifold swirl flap
OM606 2
○ MINOR
Glow plug failure (only meaningful issue)
○ MINOR
Injection pump seal wear (age-related)