Mercedes-Benz M278 4.7L Bi-Turbo Engine For Sale.

Mercedes-Benz M278 4.7L Bi-Turbo V8 Gasoline Engine

Powerful and Refined Performance Engine, used engine For Sale.

The Mercedes-Benz M278 4.7L Bi-Turbo Engine is a powerful and refined performance engine engineered to deliver robust power, smooth torque, and advanced efficiency for luxury SUV and sedan applications. 

Featuring dual turbochargers, direct fuel injection, and a DOHC (dual overhead camshaft) design, the M278 blends exhilarating performance with Mercedes’ hallmark refinement. Its sophisticated engineering makes it a highly requested used engine choice for both replacements and performance upgrades in high-end Mercedes-Benz vehicles.

This 4.7-liter bi-turbo V8 gasoline engine utilizes a lightweight aluminum block and heads combined with direct injection and variable valve timing (VVT) to optimize combustion and efficiency. Typical output for the M278 ranges between 429–449 horsepower with torque figures around 700–750 Nm, providing strong acceleration and confident overtaking power. 

The twin turbochargers help deliver immediate response across the rev range, while the advanced engine management system ensures smooth power delivery and improved fuel economy compared to traditional large-displacement V8s.

The M278 engine is widely compatible across several Mercedes-Benz model lines, making it a versatile and popular unit in the used engine marketplace. 

Common applications include the Mercedes-Benz GLE-Class (GLE450/AMG variants), S-Class (S450/S500), E-Class (E450), CLS-Class, GLS-Class, and larger ML-Class/GLE SUVs, depending on production year and regional specifications. Its integration with both rear-wheel and all-wheel drive systems, as well as a range of automatic transmissions, ensures broad fitment and ease of installation for many luxury vehicles.

Specifications, Common weaknesses and Maintenance.

Despite its advanced engineering, the M278 does have some common weaknesses that buyers should be aware of, particularly in higher-mileage units. These may include leaks from oil cooler seals or valve cover gaskets, high-pressure fuel pump (HPFP) wear, and carbon buildup on intake valves due to the direct injection system. Turbocharger component wear and PCV system issues can also occur if maintenance is deferred.

Maintenance notes are key to long-term performance and reliability. Regular high-quality synthetic oil and filter changes, periodic inspection of the fuel and cooling systems, and proactive cleaning of the intake and turbo systems are strongly recommended. Monitoring diagnostic codes and addressing minor faults early can prevent more significant issues later. When maintained properly, the Mercedes-Benz M278 4.7L Bi-Turbo Engine delivers powerful performance, smooth response, and lasting reliability, making it a premium choice for Mercedes-Benz enthusiasts and daily drivers alike.