Audi A4 B8 Window Strip Door Rear Moulding Seal Left N/S 8K0839477F

Audi A4 B8 Window Strip Door Rear Moulding Seal Left N/S is an original body component from the Window seals and mouldings group, designed for installation in the rear left door. It ensures a tight window guide, reduces wind noise, and protects the interior of the door from moisture, which translates into stable operation of the window lifting mechanism and acoustic comfort in the cabin.

Specifications and technical data

• SKU: 8K0839477F
• Mark: Audi
• Condition: Used
• OEM Part Number: 8K0839477F
• Substitutable numbers: 8K0839477F, 8K0 839 477 F
• Location on the vehicle: Rear, Left
• Part type: Window Trim
• Category: Window Seals, Gaskets & Trims

Purpose and technical function

The rear left window seal moulding in the Audi A4 B8 is responsible for properly sealing the edge of the window in the door and guiding it during opening and closing. The component works in direct contact with the glass, which is why its correct profile and flexibility are crucial for:

• limiting the ingress of water and contaminants into the door interior,
• reducing wind noise at higher speeds,
• stable window guidance in the tracks,
• reducing the risk of scratching the glass surface.

Thanks to the factory fitment for the specific body model, the correct geometry of contact with the glass and door panel is maintained, which facilitates installation and helps avoid problems typical of universal replacements.

Compatibility with Audi A4 B8

The presented seal moulding has been designed specifically for the rear left door area of the Audi A4 B8. This means that the shape, length, and mounting points are adapted to the factory door construction of this model. In practice, this translates into:

• secure seating in the mounting slot,
• proper adhesion to the window frame and panel,
• no need for modifications or forced fitting of the component.

Such a solution is particularly beneficial for post-accident repairs or when replacing worn seals, where maintaining original sealing parameters and driving comfort is a priority.

Performance characteristics and advantages

As an original component intended for Audi, the rear left window seal moulding ensures consistency with other body components. The most important benefits of using this product include:

• Stable window operation – the correct seal profile supports even window guidance in the tracks.
• Protection of the door interior – limiting moisture ingress promotes longer service life for mechanisms and electrical wiring inside the door.
• Improved acoustic comfort – proper sealing reduces cabin noise, especially during highway driving.
• Aesthetic edge finish – the moulding organizes the contact line between the glass and the panel, which affects the visual consistency of the side of the body.

The product comes from a group of body components that are exposed to weather conditions during daily use, which is why its replacement upon visible signs of wear is recommended from the point of view of durability and vehicle comfort.

Installation area and service application

The window seal moulding is intended for installation in the rear left part of the vehicle, within the rear passenger door area. It works well both for body and paint repairs after collisions and for standard service maintenance when the existing seal shows:

• cracks or loss of flexibility,
• leaks resulting in water appearing inside the door,
• excessive noise in the window area,
• play causing window vibrations while driving.

Using an original moulding allows for restoring factory window operation parameters and reducing the risk of further service interventions in this area.

If you are planning a comprehensive repair or upgrade of the window and door area in your Audi and need other components from the same group, such as additional edge seals, guide rails, or finishing profiles by the windows, check the available parts in the Audi window seals and mouldings category.

For users interested in deepening their knowledge about selecting body components, intake systems, or engine accessories in modern designs, the Global Parts guide regarding the turbocharger and intercooler in the BMW B58 unit may be helpful – you can find it in the article BMW B58 code – checklist before buying a turbocharger and intercooler, which shows how to practically approach verifying compatibility and OEM markings.