M156 vs OM654
Side-by-side reliability comparison
Higher reliability score
OM654
BEST
85/100
+25 points over M156
0
/ 100
CAUTION
M156
Mercedes-Benz
0
/ 100
BEST
OM654
Mercedes-Benz
Specifications
M156
OM654
Brand
Mercedes-Benz
Mercedes-Benz
Verdict
CAUTION
BEST
Reliability
60
85
Years
2006--2015
2016--present
Displacement
6208 cc
1950 cc
Layout
V8
I4
Type
Petrol Na
Diesel
Power
457--514 hp
150--245 hp
Known Issues
2
2
Total Risk Cost
€2,500--€7,500
€500--€1,500
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."
OM654
"Best modern MB diesel. Aluminium block, low friction. Long-distance champion."
Issues Comparison
M156 2
◆ CRITICAL
Head bolt failure (2007-2008)
▲ HIGH
Intake manifold swirl flap
OM654 2
○ MINOR
DPF — better than older MB diesels but still diesel
○ MINOR
Minor EGR fouling (best-in-class but not immune)
Models
OM654 47
B-Class
A-Class
GLA
A-Class
C-Class
C-Class
GLC
E-Class
GLC
E-Class
GLE
E-Class
C-Class
C-Class
GLC
GLC
E-Class
C-Class
E-Class
GLC
C-Class
C-Class
GLC
E-Class
CLA
A-Class
CLA
B-Class
GLA
GLA
A-Class
E-Class
S-Class
GLE
E-Class
G-Class
E-Class
G-Class
G-Class
S-Class
S-Class
S-Class
GLE
S-Class
C 220d Wagon
E 220d Wagon
GLC 220d Coupe