M273 vs OM654
Side-by-side reliability comparison
Higher reliability score
OM654
BEST
85/100
+40 points over M273
0
/ 100
AVOID
M273
Mercedes-Benz
0
/ 100
BEST
OM654
Mercedes-Benz
Specifications
M273
OM654
Brand
Mercedes-Benz
Mercedes-Benz
Verdict
AVOID
BEST
Reliability
45
85
Years
2005--2012
2016--present
Displacement
5461 cc
1950 cc
Layout
V8
I4
Type
Petrol Na
Diesel
Power
340--388 hp
150--245 hp
Known Issues
2
2
Total Risk Cost
€2,200--€5,400
€500--€1,500
Character
M273
"Same sprocket problem as M272. Powerful but risky early models."
OM654
"Best modern MB diesel. Aluminium block, low friction. Long-distance champion."
Issues Comparison
M273 2
◆ CRITICAL
Idler gear sprocket wear — same class-action as M272
○ MINOR
Spark plugs + ignition coils (8 of each)
OM654 2
○ MINOR
DPF — better than older MB diesels but still diesel
○ MINOR
Minor EGR fouling (best-in-class but not immune)
Models
M273 1
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