OM651 (early) vs OM656

Side-by-side reliability comparison

Higher reliability score
OM656 BUY 82/100
+44 points over OM651 (early)
0 / 100
AVOID OM651 (early) Mercedes-Benz
0 / 100
BUY OM656 Mercedes-Benz

Specifications

OM651 (early)
OM656
Brand
Mercedes-Benz
Mercedes-Benz
Verdict
AVOID
BUY
Reliability
38
82
Years
2008--2014
2017--present
Displacement
2143 cc
2999 cc
Layout
I4
I6
Type
Diesel
Diesel
Power
136--204 hp
243--330 hp
Known Issues
3
2
Total Risk Cost
€2,700--€7,200
€500--€2,000

Character

OM651 (early)

"Pre-2014: injectors, timing chain, DPF. Hard to work on."

OM656

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

Issues Comparison

OM651 (early) 3

◆ CRITICAL
Piezoelectric injector failure (pre-2014) €1,200--€3,500 60,000 km--130,000 km
◆ CRITICAL
Timing chain stretch (pre-2014) €1,000--€2,500 80,000 km--150,000 km
▲ HIGH
DPF + EGR fouling (city use) €500--€1,200 60,000 km--120,000 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

OM651 (early) 34

E-Class W210 1998--2002 E-Class W210 1998--2002 C-Class W202 1997--2000 C-Class W202 1998--2000 C-Class W203 2001--2007 A-Class W169 2004--2012 A-Class W169 2005--2012 A-Class W169 2004--2012 CLK W209 2005--2009 E-Class W211 2002--2009 C-Class W203 2003--2007 E-Class W211 2006--2009 E-Class W211 2002--2006 GLA X156 2014--2020 CLA C117 2013--2019 GLK X204 2010--2015 GLC X253 2015--2019 B-Class W246 2014--2018 C-Class W204 2007--2014 E-Class W212 2009--2016 E-Class W212 2009--2016 A-Class W176 2014--2018 C-Class W205 2014--2018 E-Class W212 2009--2016 GLE W166 2015--2019 GLC X253 2015--2019 C-Class W205 2014--2018 CLA C117 2013--2019 A-Class W176 2014--2018 GLK X204 2008--2015 C-Class W204 2008--2014 GLC X253 2015--2019 GLA X156 2014--2020 C-Class W204 2007--2014

OM656 3

E 400d W213 2016--2024 Sedan GLE 350d W166 2015--2019 SUV S 350d W222 2013--2020 Sedan
Full OM651 (early) Report Full OM656 Report