Wiper Arm Mercedes W177 W247 Rear Window Glass A2478206400

Wiper Arm Mercedes W177 W247 Rear Window Glass is an original component from the Wiper arms group, designed for operation on the vehicle's rear window. Engineered by the vehicle manufacturer, it ensures the correct pressure geometry of the blade against the glass and stable operation under typical operating conditions. It is a functional solution for users who expect predictable performance from the rear window cleaning system.

Specifications and technical data

• SKU: A2478206400
• Mark: Mercedes (Genuine OE)
• Condition: Used
• OEM Part Number: A2478206400
• Substitutable numbers: A2478206400, A 247 820 64 00
• Location on the vehicle: Rear
• Category: Wiper Arms

Purpose and function in the vehicle

The presented arm is a component of the rear window cleaning system, mounted in the rear body area. It is responsible for transferring motion from the drive mechanism to the wiper blade, keeping it in the correct position relative to the glass. Proper fitment to a specific body generation allows for maintaining the correct operating angle and even pressure along the entire length of the blade.

Its placement in the rear zone of the vehicle facilitates the effective removal of water, mud, and debris from the glass, which improves visibility in the rearview mirror and supports safe maneuvering, especially when reversing and driving in difficult weather conditions.

Construction and compatibility with the wiper system

The wiper arm has been designed to work with the factory drive mechanism in the given vehicle model. Properly selected mounting and arm geometry reduce the risk of vibrations, uneven blade contact, or excessive load on the drive axle. As a result, the system operates in a predictable manner, and the wear of moving parts remains at a controlled level.

The original Mercedes origin means that manufacturer standards regarding dimensional tolerances are maintained, which translates into proper fitment with the wiper axle, external covers, and the glass. In practice, this facilitates installation and minimizes the need for additional adjustments after replacement.

Condition of the component and operational aspects

The item is offered as a used part, which allows for an economical replacement while maintaining the original design. This type of solution is often chosen in situations where mechanical damage to the arm has occurred, e.g., as a result of snow load, improper use, or a collision in the rear zone of the vehicle. Using an original arm from the same design group helps maintain the consistency of the entire wiper system's operation.

Replacing the arm is a typical service operation that can be performed in a workshop, and in many cases, also at home using basic tools. A correctly selected component reduces the risk of improper blade positioning or rubbing against the edges of the glass or body elements.

Benefits of using an original wiper arm

Using an original arm in the rear window cleaning system brings a number of practical benefits:

• maintaining the correct geometry of the blade's operation on the glass,
• stable cooperation with the factory drive mechanism,
• reduction of noise and vibrations during wiper operation,
• visual consistency with other body elements,
• easier diagnostics and service in the future.

For users who want to keep the vehicle in a configuration close to the factory one, choosing an original arm from the Wiper arms group is a technically justified and predictable solution in terms of operation.

Expanding the wiper system in Mercedes vehicles

If you are planning a comprehensive repair or upgrade of the window cleaning zone in your Mercedes and need other elements from the same group, such as additional arms, mounts, or compatible components working with blades, check the available parts in the Mercedes Wiper arms category.

Expert support when choosing used components

When selecting used vehicle system components, including those working with drive mechanisms, it is worth relying on reliable technical information and identification procedures based on manufacturer markings. Additional tips on the principles of choosing used components, cost-effectiveness analysis, and methods of verifying compatibility can be found in the article Why it is worth buying used gearboxes and engines – facts instead of myths, which discusses the practical aspects of purchasing used parts based on technical data.