Mercedes-Benz is a brand synonymous with luxury, performance, and reliability. For decades, the German automaker has been at the forefront of automotive engineering, producing some of the most technologically advanced and dependable vehicles on the market. Among these vehicles, Mercedes-Benz diesel engines have garnered a reputation for their durability, efficiency, and long service life.
This post will explore the reliability of various Mercedes-Benz diesel engines available in the United States, highlighting their robust engineering and dependable performance.
The Benefits of Owning a Mercedes-Benz Diesel Car in the United States
As a Mercedes-Benz diesel engine owner in the United States, you’ll enjoy several key benefits that cater to both your driving experience and your wallet.
First and foremost, Mercedes-Benz diesel engines are known for their impressive fuel efficiency. In a time when fuel prices continue to fluctuate, having a diesel-powered vehicle can lead to significant savings at the pump, especially on long-distance drives. The increased fuel efficiency also translates to fewer trips to the gas station, providing you with more convenience and time to enjoy the open road.
Another advantage of owning a Mercedes-Benz diesel engine is the remarkable torque and power delivery. Diesel engines are known for their low-end torque, which makes them ideal for towing and carrying heavy loads. This means that whether you’re hauling a boat, driving through steep terrains, or simply accelerating onto the highway, you can count on your Mercedes-Benz diesel engine to provide a smooth and powerful driving experience.
In addition to their performance, Mercedes-Benz diesel engines are also renowned for their reliability and longevity. Thanks to their robust engineering, these engines can often surpass gasoline counterparts in terms of service life, provided they receive proper maintenance. With fewer trips to the mechanic and reduced need for repairs, you can enjoy the peace of mind that comes with owning a dependable vehicle.
Lastly, Mercedes-Benz diesel engines have made significant advancements in reducing emissions and meeting strict environmental standards. Modern diesel engines are equipped with advanced technologies such as selective catalytic reduction (SCR) and diesel particulate filters (DPF), which help to minimize the environmental footprint of these vehicles. With that said, here is reliability information for some of the most common Mercedes diesel engines in the United States.
OM642 – 3.0L V6 Turbo Diesel
The OM642 engine is a 3.0-liter V6 turbo diesel engine that powers various Mercedes-Benz models, including the E-Class, GLE, and Sprinter vans. With a reputation for its low-end torque and smooth power delivery, the OM642 is known for its fuel efficiency and long service life.
Its reliability is attributed to its strong aluminum block with cast iron cylinder sleeves, aluminum cylinder heads, and a common-rail direct fuel injection system. The engine also features a variable nozzle turbocharger and exhaust gas recirculation system, which helps to reduce emissions and improve fuel economy.
Common Issue: Oil Cooler Leaks
Cause: The oil cooler seals can deteriorate over time, leading to oil leaks. This can result in oil contamination and potential damage to other engine components.
Known Fix: Replacing the oil cooler seals and ensuring the oil cooler is properly seated can resolve this issue. Regular maintenance and oil changes can help prevent this problem from occurring.
Common Issue: Selective Catalytic Reduction Module Codes 16F600 and 16F700
Cause: One of the common causes for Selective Catalytic Reduction module codes is low AdBlue fluid. However, these modules are also known to fail from time to time.
Known Fix: Check AdBlue levels and reset the code. Alternatively, replace the SCR module and reset the codes.
Common Issue: Intake Manifold Swirl Flap Failure
Cause: The OM642 engine features swirl flaps in the intake manifold that help improve low-speed torque and combustion. However, these flaps can wear out and fail, leading to reduced engine performance.
Known Fix: Replacing the intake manifold or repairing the swirl flaps can resolve this issue. Regular maintenance and inspections can help detect potential problems early.
OM651 – 2.1L 4-Cylinder Turbo Diesel
The OM651 engine is a 2.1-liter 4-cylinder turbo diesel engine that has been used in various Mercedes-Benz models, including the C-Class, E-Class, and GLK. This engine is known for its strong performance, fuel efficiency, and low emissions.
The engine’s reliability is due in part to its two-stage turbocharging system, which allows for smooth power delivery and reduced turbo lag. The OM651 also features a common-rail direct fuel injection system, which helps to improve combustion and reduce emissions.
Common Issue: Faulty Diesel Exhaust Fluid pump
Cause: Diesel Exhaust Fluid pumps on cars fitted with the OM651 engine are known to cause issues due to DEF fluid contamination. If the pump fails, you will get one of the following diagnostic codes DTC 20E823, P20E8, P20E821, or P20E823.
Known Fix: Test the DEF pump using a scanner tool that can provide pump activation data. If the pump shows no signs of life, replace the DEF pump.
Common Issue: Injector Failure
Cause: Injector failure can be caused by poor fuel quality, debris in the fuel system, or manufacturing defects. This can result in poor engine performance, misfires, and increased emissions.
Known Fix: Replacing the faulty injector(s) and ensuring the use of high-quality fuel can resolve this issue. Regular maintenance and fuel filter changes can help prevent injector problems.
Common Issue: Timing Chain Stretch
Cause: Over time, the timing chain in the OM651 engine can stretch, leading to incorrect timing and potential engine damage.
Known Fix: Replacing the timing chain, tensioner, and associated components can resolve this issue. Regular oil changes and engine maintenance can help prolong the life of the timing chain.
OM617 – 3.0L 5-Cylinder Diesel
The OM617 engine is a legendary 3.0-liter 5-cylinder diesel engine that powered various Mercedes-Benz models, including the 300D, 300SD, and 300TD, from the late 1970s to the late 1980s. Although this engine is no longer in production, it remains an icon of reliability and durability.
The OM617 is known for its cast iron cylinder block, cast iron cylinder head, and indirect fuel injection system. With proper maintenance, these engines are known to last well over 300,000 miles, with some even reaching the one million-mile mark
Common Issue: Vacuum Pump Failure
Cause: The vacuum pump in the OM617 engine is responsible for providing vacuum to various systems, including the brakes and transmission. Over time, the vacuum pump can wear out and fail, leading to reduced performance and potential safety issues.
Known Fix: Replacing the vacuum pump and ensuring proper maintenance can resolve this issue. Regular inspections can help detect potential vacuum pump problems early.
Common Issue: Glow Plug Failure
Cause: Glow plugs in the OM617 engine can fail due to age, manufacturing defects, or excessive carbon buildup. This can result in hard starting, especially in cold weather, and reduced engine performance.
Known Fix: Replacing the faulty glow plugs and ensuring proper engine maintenance can resolve this issue. Regular glow plug inspections can help detect potential problems early.
Get Mercedes Diesel Parts at eEuroparts.com!
Mercedes-Benz diesel engines have consistently proven their reliability and durability throughout the years. Their innovative engineering, advanced fuel injection systems, and focus on fuel efficiency and low emissions contribute to their long service life and dependable performance.
For those considering a Mercedes-Benz diesel vehicle, rest assured that you are investing in a vehicle with an engine built to stand the test of time. That said, all cars need maintenance, including reliable Mercedes diesel models. If you’re looking for quality parts for your Mercedes-Benz, head over to our store and find a wide selection of premium diesel engine components!
