Mercedes W166 Rear Door Window Sealing Rail Seal Gasket Left N/S A1667300124

Mercedes W166 Rear Door Window Sealing Rail Seal Gasket Left N/S is an original body component from the Window seals and moldings group, designed for installation in the rear left door. The precisely fitted sealing profile helps reduce noise, improves acoustic comfort, and supports the protection of the interior against moisture and contaminants.

Specifications and technical data

• SKU: A1667300124
• Mark: Mercedes (Genuine OE)
• Condition: Used
• OEM Part Number: A1667300124
• Substitutable numbers: A1667300124, A 166 730 01 24
• Location on the vehicle: Rear, Left
• Category: Window Seals, Gaskets & Trims

Purpose and function of the seal

The rear left door window seal in W166 series models is responsible for the tight guidance of the window and stable sealing of the contact between the glass and the door frame. The component is installed in the rear left door area, where it:

• limits the ingress of rainwater into the door interior,
• reduces wind noise at higher speeds,
• supports the proper operation of the window lifting mechanism,
• protects the edge of the glass against excessive mechanical wear.

Thanks to the factory fit for the Mercedes body, the seal works with the original guides and door fittings, which promotes the stable operation of the entire window assembly.

Compatibility and fit for Mercedes W166

The offered seal has been designed specifically for the W166 platform, which means maintaining the correct geometry, cross-section, and working length. The Mercedes brand guarantees compliance with factory assembly standards, as well as appropriate material stiffness and flexibility in the contact zone with the glass and door frame.

The component is intended for installation on the rear left side, which eliminates the need for any modifications or adjustments on the vehicle. Proper placement of the seal in the mounting channel allows for maintaining the body line and the aesthetic appearance of the window edge.

Condition, performance properties, and installation

The seal comes from disassembly, which allows for maintaining the original manufacturer's specification at a more favorable cost compared to a new component. This is particularly important for vehicles where maintaining material and structural consistency of all seals is a priority.

During installation, it is recommended to:

• thoroughly clean the mounting channel in the door,
• check the condition of the window guides and the lifting mechanism,
• verify the window operation after installation – full range of motion without jamming or excessive resistance.

A correctly installed seal contributes to stable window operation and reduces the risk of window fogging and dampness of the upholstery in the rear part of the cabin.

Application in the body system and driving comfort

In Mercedes W166 class vehicles, body tightness has a direct impact on acoustic and thermal comfort. The rear left door window seal creates a barrier between the interior and the environment, which:

• reduces the penetration of noise from the outside into the rear of the cabin,
• supports the maintenance of a stable temperature inside the vehicle,
• limits the risk of corrosion of metal components inside the door.

For users who pay attention to the bodywork refinement and the comfort of passengers in the back seat, replacing a worn seal with an original component from the same series is a technically justified solution.

Modernization expansion – Mercedes window seals and moldings

If you are planning a comprehensive repair or modernization of the door and side window area in your Mercedes and need other components from the same group, such as additional window seals, window moldings, or door frame seals, check the available parts in the Mercedes window seals and moldings category.

Technical support and part selection

When selecting a seal for a specific body version, it is worth paying attention to the installation side and the door type. Original manufacturer markings facilitate the verification of compatibility with the vehicle, and comparing the shape and length with the removed component helps avoid installation errors.

Additional information on the professional selection of body components, diagnostic methods, and the importance of original markings can be found in the article: Fuel system – injectors, pumps, and fuel tank: maintenance and regeneration, which discusses practical principles of working with parts identified by OEM and reference numbers.