OM656
Mercedes-Benz · 3.0L Diesel I6
2017–present
"Flagship modern MB diesel. Inline-6 smoothness returns. MHEV. GLE/GLS/S-Class. Excellent highway. Early data strong."
Mileage Risk Timeline
When problems typically appear — enter your mileage to see your risk zone
Known Issues 2
DPF + EGR — diesel city driving concern
▸DPF warning, EGR codes, limp mode
Modern diesel: better than older MB units but city-only use still causes DPF/EGR fouling.
OM656 in E-Class GLE: mixed use drivers fine. Athens city-only: consider petrol M256 instead.
AdBlue / SCR system consumption and faults
▸AdBlue warning, SCR faults, NOx system alerts
Modern Euro 6 diesel with full SCR/AdBlue system. AdBlue needs topping every 10-15k km.
AdBlue widely available at Greek stations. System fault diagnosis needs Mercedes specialist.
Models with OM656 3
Other Mercedes-Benz Engines
Tuning Potential
300hp Stage 1
Frequently Asked Questions
Is the Mercedes-Benz OM656 reliable?
The Mercedes-Benz OM656 scores 82/100 with a verdict of BUY. It has 2 documented issues with total repair costs between €500 and €2,000.
What are the common problems with the OM656?
The most common issues are:
- DPF + EGR — diesel city driving concern — moderate, repair cost €400–€1,200, 60,000 km–120,000 km
- AdBlue / SCR system consumption and faults — minor, repair cost €100–€800, 30,000 km–∞
What cars use the Mercedes-Benz OM656?
How much does it cost to repair the OM656?
Total potential repair costs for all 2 known issues range from €500 to €2,000. The most expensive issue is typically .
What years was the OM656 produced?
The Mercedes-Benz OM656 was produced from 2017 to present. It is a 2999cc I6 diesel engine.
Verdict and scores are editorial opinions based on aggregated data. Learn about our methodology. Not a substitute for professional inspection.