M273 vs OM656

Side-by-side reliability comparison

Higher reliability score
OM656 BUY 82/100
+37 points over M273
0 / 100
AVOID M273 Mercedes-Benz
0 / 100
BUY OM656 Mercedes-Benz

Specifications

M273
OM656
Brand
Mercedes-Benz
Mercedes-Benz
Verdict
AVOID
BUY
Reliability
45
82
Years
2005--2012
2017--present
Displacement
5461 cc
2999 cc
Layout
V8
I6
Type
Petrol Na
Diesel
Power
340--388 hp
243--330 hp
Known Issues
2
2
Total Risk Cost
€2,200--€5,400
€500--€2,000

Character

M273

"Same sprocket problem as M272. Powerful but risky early models."

OM656

"Flagship modern MB diesel. Inline-6 smoothness returns. MHEV. GLE/GLS/S-Class. Excellent highway. Early data strong."

Issues Comparison

M273 2

◆ CRITICAL
Idler gear sprocket wear — same class-action as M272 €1,800--€4,500 60,000 km--150,000 km
○ MINOR
Spark plugs + ignition coils (8 of each) €400--€900 80,000 km--150,000 km

OM656 2

● MODERATE
DPF + EGR — diesel city driving concern €400--€1,200 60,000 km--120,000 km
○ MINOR
AdBlue / SCR system consumption and faults €100--€800 30,000 km--∞

Models

M273 1

S-Class W221 2006--2011

OM656 3

E 400d W213 2016--2024 Sedan GLE 350d W166 2015--2019 SUV S 350d W222 2013--2020 Sedan
Full M273 Report Full OM656 Report