M278
Mercedes-Benz · M278 4.7 V8 Biturbo
2010–2018
"W222 S500, W166 GLE500, W212 E550. Hot-V twin-turbo. Timing chain guides. Turbo oil line leaks. Expensive timing chain job (engine-out in some models). Powerful but costly to own."
Mileage Risk Timeline
When problems typically appear — enter your mileage to see your risk zone
Known Issues 2
Timing chain guide failure
▸Rattle, timing codes
Hot-V chain guides degrade from heat. Engine-out job on some models.
Αλυσίδα Hot-V — €2,000-8,000. ΣΟΒΑΡΟ.
Turbo oil line leak
▸Oil leak, smoke, fire risk
Oil feed lines to turbos leak.
Σωλήνες λαδιού turbo — €500-1,500.
Models with M278 2
Related Guides
Other Mercedes-Benz Engines
Tuning Potential
550hp Stage 1
Frequently Asked Questions
Is the Mercedes-Benz M278 reliable?
The Mercedes-Benz M278 scores 62/100 with a verdict of CAUTION. It has 2 documented issues with total repair costs between €2,500 and €9,500.
What are the common problems with the M278?
The most common issues are:
- Timing chain guide failure — critical, repair cost €2,000–€8,000, 80,000 km–150,000 km
- Turbo oil line leak — high, repair cost €500–€1,500, 60,000 km–120,000 km
How much does it cost to repair the M278?
Total potential repair costs for all 2 known issues range from €2,500 to €9,500. The most expensive issue is typically .
What years was the M278 produced?
The Mercedes-Benz M278 was produced from 2010 to 2018. It is a 4663cc V8 petrol turbo engine.
Scores are calculated from documented issues, repair costs, and failure patterns across thousands of owner reports and technical sources. Learn about our methodology. Always inspect before you buy.