Audi A4 S4 RS4 8W B9 Door Seal Gasket Rubber Front Left Right N/O/S 8W0831721B

Audi A4 S4 RS4 8W B9 Door Seal Gasket Rubber Front Left Right is an original component from the Door seals group, designed for use in the front doors on either the driver or passenger side in Audi A4, S4, and RS4 models of the B9 generation. The precisely molded rubber profile helps reduce noise, improves cabin sealing, and supports the proper operation of the doors during daily use.

Specifications and technical data

• SKU: 8W0831721B
• Mark: Audi
• Condition: Used
• OEM Part Number: 8W0831721B
• Substitutable numbers: 8W0831721B, 8W0 831 721 B, 8W0831721C, 8W0 831 721 C
• Location on the vehicle: Front, Left, Right
• Part type: Door Seal
• Category: Door Seals

Purpose and vehicle placement

The presented seal is designed for installation on the front door on the left or right side, allowing for flexible use of the component during body repairs. The design, tailored to the B9 generation, ensures proper adhesion to the door frame and body, which translates into stable door movement and limits the penetration of water and contaminants.

Technical and functional characteristics

The rubber structure of the seal has been developed to work in variable weather conditions typical for vehicle operation in Europe. The appropriately selected material hardness supports:

• damping vibrations transmitted from the body to the door,
• reduction of wind noise at higher speeds,
• maintaining the seal of the door circuit within the temperature ranges encountered in road traffic.

The original fitment to the Audi B9 platform facilitates installation in place of the factory seal, without the need to modify the door edges or the body. As a result, the component works well with locks, hinges, and other door zone components.

Condition of the item and service application

The seal comes from dismantling and is offered as a used original Audi component, which allows for maintaining factory fitment and door operating characteristics. This type of component is particularly useful for:

• repairs after collisions in the front door area,
• eliminating leaks and wind whistling in the cabin,
• renovation of the door zone in vehicles operated in difficult conditions.

Using an original rubber seal helps maintain the structural integrity of the body and preserve acoustic comfort inside the vehicle at a level close to factory standards.

Benefits of using an original Audi seal

Choosing an item from the Door seals group dedicated to the Audi A4, S4, and RS4 B9 allows you to reduce the risk of fitment problems typical of universal replacements. The appropriate profile and cross-section geometry support proper door closing as well as stable retention of the seal on the edge. This is a beneficial solution both for a single replacement and for broader body and paint work in the front part of the body.

Expanding work within Audi door seals

If you are planning a comprehensive repair or upgrade of the door zone in your Audi and need other elements from the same group, such as additional rubber profiles, perimeter seals, or door sill sealing elements, check the available parts in the Audi door seals category.

When planning broader service work on the vehicle, it is also worth checking out practical tips regarding the selection of used mechanical components – you can find helpful information in the article Used gearbox – when is it worth it and what you need to remember.