M274 vs OM656

Side-by-side reliability comparison

Higher reliability score
OM656 BUY 82/100
+10 points over M274
0 / 100
ACCEPTABLE M274 Mercedes-Benz
0 / 100
BUY OM656 Mercedes-Benz

Specifications

M274
OM656
Brand
Mercedes-Benz
Mercedes-Benz
Verdict
ACCEPTABLE
BUY
Reliability
72
82
Years
2012--2019
2017--present
Displacement
1991 cc
2999 cc
Layout
I4
I6
Type
Petrol Turbo
Diesel
Power
184--211 hp
243--330 hp
Known Issues
3
2
Total Risk Cost
€2,150--€5,400
€500--€2,000

Character

M274

"Improved over M271. Dual-row chain. Thermostat main issue. Reliable with care."

OM656

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

Issues Comparison

M274 3

▲ HIGH
Oil consumption — piston ring design (early units) €1,500--€4,000 60,000 km--120,000 km
● MODERATE
Thermostat failure €250--€500 60,000 km--130,000 km
● MODERATE
Camshaft adjuster / actuator noise €400--€900 80,000 km--160,000 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

M274 12

C-Class W205 2014--2018 E-Class W212 2013--2016 GLK X204 2012--2015 GLC X253 2015--2019 E-Class W212 2013--2016 GLC X253 2015--2019 C-Class W205 2014--2018 E-Class W213 2016--2020 E-Class W213 2016--2020 C-Class W205 2014--2018 C 200 Wagon S205 2014--2021 Wagon GLC 200 Coupe C253 2016--2023 SUV

OM656 3

E 400d W213 2016--2024 Sedan GLE 350d W166 2015--2019 SUV S 350d W222 2013--2020 Sedan
Full M274 Report Full OM656 Report