Audi A4 S4 Rs4 8K RS4 B8 Rear Inner Door Seal Rubber Gasket Left Right N/O/S

Audi A4 S4 Rs4 8K RS4 B8 Rear Inner Door Seal Rubber Gasket Left Right N/O/S is an original component from the Door seals group, designed for installation on the rear axle of the vehicle on either the left or right side. The carefully designed rubber profile helps reduce noise, improves cabin sealing, and supports the protection of the interior against moisture and contaminants.

Specifications and technical data

• SKU: 8K9833721J
• Mark: Audi
• Condition: Used
• OEM Part Number: 8K9833721J
• Substitutable numbers: 8K9833721J, 8K9 833 721 J
• Location on the vehicle: Rear, Right, Left
• Part type: Door Seal
• Category: Door Seals

Purpose and function of the seal

The presented rear inner door seal rubber was developed specifically for the A4, S4, and RS4 models of the B8 generation. Its task is to create a stable, flexible barrier between the door edge and the body, which translates into better acoustic insulation, reduction of drafts, and more comfortable conditions in the cabin while driving in various weather conditions.

The placement on the vehicle covers the rear part of the body on the left and right sides, allowing the element to be used both for replacing a single seal and for symmetrical renovation of both rear doors. The rubber construction ensures appropriate flexibility while maintaining stable adhesion to the edge, which promotes maintaining uniform pressure along the entire circumference of the door.

Benefits of using an original Audi seal

Using an original seal dedicated to specific Audi models allows for maintaining factory fitment and predictable material behavior over a long period of operation. In practice, this means:

• more uniform closing of the rear doors without excessive resistance,
• reduction of water and dust penetration into the interior,
• reduction of wind noise levels at higher speeds,
• maintaining the aesthetic appearance of the door edges and adjacent upholstery elements.

Thanks to the fitment to the specific body geometry of the A4, S4, and RS4 B8 series, the seal works with factory mounting points, which facilitates installation and avoids problems typical of universal replacements. This solution is particularly beneficial for precise door adjustments, where repeatability and predictable material behavior count.

Material and performance characteristics

The rubber construction of the seal has been selected for operation in the typical temperature range encountered in passenger car operation. The material is resistant to frequent opening and closing of doors, as well as to standard agents used for body care. A properly shaped cross-section supports water drainage from the door edge and reduces the risk of it stagnating in critical areas.

As an element from the Door seals category, the product fits into the cabin protection system against external factors, working with other body seals. Proper selection and installation of this seal helps maintain stable operating conditions for upholstery elements, electrical installations in the doors, and lock mechanisms.

Condition, installation, and service application

The seal is offered as a used item, which allows for an economical replacement of a worn or damaged component while maintaining the manufacturer's original specification. This type of solution is particularly useful for post-accident repairs, body renovation, or restoring factory sealing after many years of vehicle operation.

In practice, installation comes down to correctly seating the seal in the intended profile on the edge of the door or body, while maintaining continuity along the entire circumference. Proper positioning of the material is crucial for obtaining uniform pressure and avoiding local leaks, so it is worth paying attention to the course of corners and contact points with other sealing elements.

Expansion of service work scope

If you are planning a comprehensive repair or modernization of the rear door area in your Audi and need other elements from the same group, such as additional edge seals, inner rubber profiles, or supplementary sealing sections, check the available parts in the Audi door seals category.

Choosing original used components can also be a conscious pro-ecological decision. If you want to learn more about the impact of such solutions on the environment and learn the arguments for reusing parts from dismantling, read the article Sustainable automotive: How buying original used parts reduces the carbon footprint and protects the environment?.