Mercedes ML W166 OM651 Diesel EGR Gas Recirculation Pipe Hose Tube A6511402008

Mercedes ML W166 OM651 Diesel EGR Gas Recirculation Pipe Hose Tube is an exhaust system component designed for diesel engines, responsible for precisely directing exhaust gases to the EGR valve. By maintaining factory geometry and flow diameter, it ensures stable operating conditions for the power unit and supports emission reduction. This is a practical solution for users who want to restore the proper functioning of the exhaust gas recirculation system in their Mercedes.

Specifications and technical data

• SKU: A6511402008
• Mark: Mercedes (Genuine OE)
• Condition: Used
• OEM Part Number: A6511402008
• Substitutable numbers: A6511402008, A 651 140 20 08
• Location on the vehicle: Front
• Fuel type: Diesel
• Category: EGR Parts & Valves

Purpose and function in the EGR system

The exhaust gas recirculation pipe in the ML W166 model with the OM651 engine operates in the front part of the vehicle, connecting exhaust system components to the EGR valve. It is responsible for the controlled transport of exhaust gases for reintroduction into the combustion chamber, which helps limit nitrogen oxide emissions and improve the refinement of the diesel engine.

A properly selected EGR pipe is particularly important in Diesel units, where the exhaust gas recirculation system has a direct impact on operating parameters, idle stability, and compliance with emission standards. Using a dedicated component for the OM651 minimizes the risk of leaks, ECU errors, and performance drops.

Benefits of using a dedicated EGR pipe

Selecting the right exhaust gas recirculation pipe for a specific Mercedes model translates into a number of practical operational benefits:

• maintaining proper exhaust gas flow in the EGR system,
• reducing the risk of errors related to exhaust gas recirculation,
• more stable engine operation across the full load range,
• better compatibility with the factory engine control unit,
• maintaining compliance with the manufacturer's design specifications.

For users looking for solutions with a favorable price-to-quality ratio, it is important that the used OEM component retains the original flow characteristics and mounting fit, which facilitates service and shortens repair time.

Mounting characteristics and fitment

The EGR exhaust gas recirculation pipe designed for the Mercedes ML W166 with the OM651 engine has been engineered for specific mounting points in the front of the vehicle. As a result, installation is straightforward, without the need for modifications or forcing the component into place.

In practice, this means:

• secure seating in factory brackets and mounts,
• correct routing of the pipe relative to other components in the engine bay,
• reduced risk of vibrations and stresses that could lead to leaks.

Such fitment is particularly important in high-temperature systems, where the stability of connections has a direct impact on the durability of the entire exhaust gas recirculation system.

Why choose an element from the EGR Valves and Parts category

Components from the EGR Valves and Parts group operate under demanding thermal and chemical conditions, which is why their selection is important for long-term engine reliability. The exhaust gas recirculation pipe dedicated to the OM651 unit in the ML W166 has been developed to work with the factory EGR valve and other exhaust system components.

Using the correct elements in this area allows you to:

• maintain stable combustion parameters in the diesel engine,
• reduce the risk of excessive carbon deposit buildup in the system,
• limit the need for frequent service interventions.

Expanding the EGR system in your Mercedes

If you are planning a comprehensive repair or upgrade of the engine area in your Mercedes and need other components from the same group, such as hoses, pipes, or valve bodies, check out the available parts in the EGR Valves and Parts Mercedes category.

Used EGR components and purchase cost-effectiveness

In the case of exhaust gas recirculation systems, many users consider choosing used parts, especially when they want to maintain the original manufacturer's specifications while reducing costs. A used EGR pipe for a Mercedes ML W166 with an OM651 engine can be a reasonable compromise between price and functionality, provided it is correctly selected for the specific engine version.

If you want to analyze the topic of cost-effectiveness of purchasing second-hand components more broadly and compare them with new replacements, the following article discussing cost and quality differences may be helpful: comparison of costs and quality of new and used parts.

More about used parts and informed choices

An informed approach to purchasing used components, such as exhaust gas recirculation pipes, allows you to optimize your service budget without sacrificing the factory operating characteristics of the system. It is worth paying attention to the compatibility of the component with the specific model and engine type, as well as ensuring it comes from a reliable source.

Additional tips on what to look for when choosing parts from the secondary market can be found in our guide: is it worth investing in used parts and what are their key advantages.