Engine Mount Mercedes W212 OM651 Gearbox Transmission Support A2122404202

The Automatic Transmission Engine Mount for Mercedes W212 OM651 is an original, factory-made transmission support, specifically designed to work with the OM651 engine and an automatic gearbox. This component, categorized under Engine Mounts, is responsible for the stable mounting of the powertrain, vibration reduction, and improving the driving refinement of your Mercedes. Its precise design ensures predictable drivetrain behavior and comfortable operation of the automatic transmission.

Specifications and technical data

• SKU: A2122404202
• Mark: Mercedes (Genuine OE)
• Condition: Used
• OEM Part Number: A2122404202
• Substitutable numbers: A2122404202, A 212 240 42 02
• Gearbox type: Automatic
• Category: Engine Mounts

Purpose and Function in the Drivetrain

The described mount acts as a gearbox support, transferring loads from the automatic transmission to the vehicle body while simultaneously dampening vibrations generated by the OM651 engine. Appropriately selected stiffness and mounting geometry help maintain the correct position of the gearbox, which is crucial for the operation of drive shafts, half-shafts, and control elements.

Using the correct, original transmission support is particularly important in vehicles with automatic transmissions, where improper support can lead to:

• increased vibrations felt in the cabin,
• undesirable noises during gear changes,
• excessive stress on other powertrain mounts.

Benefits of Using an Original Engine Mount

Using a factory-made transmission mounting component in a Mercedes W212 with an OM651 engine and automatic transmission offers a range of practical operational benefits:

• Precise Fit – designed for a specific drivetrain configuration, eliminating the need for modifications or adjustments.
• Stable Automatic Transmission Operation – proper support limits uncontrolled powertrain movements, contributing to smoother gear changes.
• Improved Vibration Isolation – appropriately selected damping properties enhance driving comfort and reduce vibration transfer to the vehicle body.
• Consistency with Factory Powertrain Suspension Characteristics – maintaining the parameters intended by the vehicle manufacturer.

Mounting Characteristics

The mount is designed as a component intended for installation in place of the factory transmission support in the Mercedes E-Class W212 generation with the OM651 unit. The design anticipates cooperation with an automatic transmission, which simplifies servicing and reduces the risk of mounting geometry issues. In practice, this means the component can be used as a replacement for a worn mount within standard workshop procedures.

Before installation, it is recommended to verify the part's compatibility with the vehicle based on the OEM number and interchangeable numbers in the service documentation or manufacturer's catalog, as well as to inspect other powertrain mounts to ensure even load distribution across all support points.

Condition and Service Application

The offered automatic transmission engine mount is a used part, intended for service applications as a replacement for the factory mounting in Mercedes vehicles with the OM651 engine. This type of part allows for economical drivetrain repair while maintaining the original construction and operating characteristics of the mount. Replacement of a worn mount is recommended if excessive vibrations, knocking during acceleration or gear changes, and visible damage to the rubber-metal damping elements occur.

If you are planning a comprehensive repair or upgrade of the engine and transmission area in your Mercedes and need other parts from the same group, such as additional mounts, supports, or vibration damping elements, check the available parts in the Mercedes Engine Mounts category.

More About Fuel and Exhaust Emission System Components

When working on the powertrain, it is also worth paying attention to components responsible for exhaust emissions and engine efficiency. To broaden your knowledge of one of the key systems, consider reading the article EGR: What it is and why consider used EGR valves, which discusses the operating principle of the exhaust gas recirculation system and practical aspects of selecting used components.