Mercedes-Benz OM642 3.0L Turbo-Diesel Engine.

Mercedes-Benz OM642 3.0L V6 Common-Rail Turbo-Diesel Engine.

legendary Respected Powerplant , Used engine For Sale.

The Mercedes-Benz OM642 3.0L Turbo-Diesel Engine is a highly respected powerplant known for its strong torque, efficient performance, and robust engineering. Designed as a modern diesel option for a wide range of Mercedes vehicles, the OM642 combines advanced common-rail fuel injection with turbocharging to deliver smooth, responsive drivability and excellent fuel economy.

Its aluminum block and cylinder heads help reduce overall weight while maintaining durability, making it a sought-after choice in the used engine market for replacements, upgrades, and rebuilds.

This 3.0-liter V6 turbo-diesel engine features a common-rail direct injection system paired with a variable geometry turbocharger (VGT), delivering excellent combustion efficiency and strong low-end torque. Typical power output for the OM642 ranges from 190–225 horsepower, and also with torque figures of approximately 400–620 Nm, depending on model year and tuning. 

The engine’s broad torque curve provides confident acceleration, strong towing capability, and reliable performance across highway and urban driving conditions. Equipped with a timing chain rather than a belt, the OM642 often experiences lower long-term maintenance costs and improved durability.

The OM642 engine was widely used across Mercedes-Benz’s lineup and is however compatible with numerous models, making it one of the most versatile used diesel engines available. 

Common applications include the Mercedes-Benz E-Class (E320 CDI, E350 BlueTEC), ML-Class (ML320/ML350 CDI), GL-Class (GL320/GL350 CDI), R-Class (R320/R350 CDI), S-Class (S320 CDI), Sprinter vans, and moreover various commercial applications. This broad compatibility ensures the OM642 remains in high demand for both passenger vehicles and larger SUVs or vans requiring a capable diesel engine.

 Specifications, Common weaknesses and Maintenance.

While the OM642 is generally reliable, it does have some common weaknesses potential buyers should be aware of. These include crankshaft sprocket wear on early engines, balance shaft issues, EGR cooler clogging, and turbocharger wear after high mileage. Diesel particulate filter (DPF) blockages can also occur, particularly in vehicles used primarily for short trips.

Maintenance notes emphasize regular high-quality diesel oil and filter changes, timely inspection of the cooling system, and monitoring of the EGR and DPF systems to prevent build-up. Ensuring proper engine tuning and servicing the turbocharger and injection components enhances longevity and performance. 

When well maintained, the Mercedes-Benz OM642 3.0L V6 diesel engine delivers durability, strong torque, and excellent real-world efficiency, making it an excellent investment for Mercedes owners and commercial fleet operators alike.