Mercedes W639 W906 Engine Oil Pump Lubrication Unit OM651 A6511801400

Mercedes W639 W906 Engine Oil Pump Lubrication Unit is an original component from the Oil pumps and parts group, designed for Mercedes engines from the OM651 family used in models such as the W639 and W906. This used oil pump allows for a technically sound and cost-effective replacement of the factory component, while maintaining the proper lubrication parameters of the engine.

Specifications and technical data

• SKU: A6511801400-2
• Mark: Mercedes (Genuine OE)
• Condition: Used
• OEM Part Number: A6511801400
• Substitutable numbers: A6511801400, A 651 180 14 00, A6511811801, A 651 181 18 01, A6511801301, A 651 180 13 01, A6511810512, A 651 181 05 12, A6511810312, A 651 181 03 12, A 651 180 26 01, A6511802601, A 651 180 28 01, A6511802801, A 651 180 04 00, A6511800400
• Fuel type: Petrol
• Part type: Oil Pump
• Category: Oil Pumps & Parts

Purpose and function of the oil pump

The oil pump in the OM651 engine is responsible for the forced lubrication of all key engine components, such as the crankshaft, camshafts, and the timing system. A properly functioning lubrication system reduces friction, stabilizes operating temperature, and affects engine longevity, which is particularly important in heavily used commercial and passenger vehicles. The presented pump is structurally matched to these engines, ensuring compliance with the pressure and flow characteristics required by the OM651 unit. This allows for the maintenance of stable oil pressure across the full range of loads and engine speeds.

Installation compatibility and interchangeable numbers

The oil pump was designed as an OEM component for a specific engine family, and its design allows for the use of various interchangeable numbers within the same parts group. The presence of multiple reference numbers in the technical specification facilitates the selection of the correct variant for a specific vehicle configuration, which is crucial when servicing models produced over several years. Thanks to this solution, a mechanic or user can verify the compatibility of the part with their vehicle by relying on the OEM part number and the interchangeable numbers visible in the specification section. This approach minimizes the risk of selecting an incorrect component and speeds up the repair process.

Usage characteristics and benefits of choosing this part

As a used component, the oil pump represents a reasonable compromise between repair costs and maintaining the manufacturer's original design. In practice, this means the ability to restore proper engine lubrication without the need to invest in a new component, while maintaining factory geometry and mounting methods. Key advantages of this solution include:

• preservation of the original design of the OM651 engine lubrication system,
• compatibility with factory oil channels and engine accessories,
• the possibility of an economical repair while maintaining high system functionality. For vehicles used intensively, including commercial vans, choosing a used oil pump can be an effective way to extend engine life while keeping service costs under control.

Mercedes oil pumps and parts – expansion and service

If you are planning a comprehensive repair or upgrade of the engine area in your Mercedes and need other elements from the same group, such as pump housings, drive gears, or mounting elements, check out the available parts in the Mercedes oil pumps and parts category.

Support in selecting used parts

When planning an engine repair in an older Mercedes, especially from years close to youngtimers, it is worth knowing the broader context of using pre-owned components. Practical tips on refreshing vehicles from this period, including Mercedes models, can be found in the article Second life of a youngtimer – how used car parts rejuvenate cars from the 1998–2012 era. If you are considering whether a new or used oil pump is a better choice in your case, comparing the costs and durability of different solutions described in the guide Car parts – new or used? We compare costs, quality, and durability may be helpful.