Audi A4 S4 B7 Brake Fluid Reservoir Screw Filler Tank Cap 6N1611349B

Audi A4 S4 B7 Brake Fluid Reservoir Screw Filler Tank Cap is an original component from the Brake servos and pressure regulators group, designed for the braking system of Audi vehicles. It is a practical solution for users who want to maintain the factory performance characteristics of the braking system and ensure the appropriate level of vehicle operational safety.

Specifications and technical data

• SKU: 6N1611349B
• Mark: Audi
• Condition: Used
• OEM Part Number: 6N1611349B
• Substitutable numbers: 6N1611349B, 6N1 611 349 B
• Category: Brake Servos

Purpose and function in the braking system

The brake fluid reservoir cap in an Audi is responsible for sealing the reservoir and maintaining the stability of the working medium within the system. A properly selected cap helps limit the ingress of moisture and contaminants, which helps maintain brake fluid parameters at the correct level and supports the proper operation of the brake servo and pressure regulators.

Using an original component from this group allows for compliance with the factory design of the braking system, which is particularly important for precisely tuned models such as the Audi A4 or S4 of the B7 generation.

Technical characteristics and fitment

The cap has been designed as an OEM part, ensuring that its geometry, mounting method, and interaction with other braking system components are consistent with the manufacturer's factory specifications. Carefully selected materials provide resistance to brake fluid and the typical thermal conditions found in the engine compartment.

The element is intended for installation in place of the factory cap, which allows for maintaining the original routing of lines, proper reservoir venting, and correct interaction with the brake servo and pressure regulators. Such fitment reduces the risk of leaks and facilitates system maintenance.

Product condition and service application

The offered brake fluid reservoir cap is an aftermarket element, which allows for an economical replacement of a worn or damaged cap while maintaining the manufacturer's original specifications. It is a practical solution in situations where the existing component shows signs of wear, mechanical damage, or issues with sealing.

Replacing the cap is recommended, among other things, during service work related to the braking system, such as fluid replacement, brake servo regeneration, or maintenance of pressure regulators. Using an original component helps maintain the integrity of the entire system and reduces the risk of operational issues.

Benefits of using the original cap

• Factory fitment for the Audi braking system, with no modifications required.
• Consistency with the Brake servos and pressure regulators group of components, which facilitates diagnostics and service.
• Reduced risk of brake fluid reservoir leaks.
• Support for stable braking system operation in daily use.

If you are planning a comprehensive repair or upgrade of the braking zone in your Audi and need other components from the same group, such as a brake servo, pressure regulator, or additional elements working with the vacuum system, check the available parts in the Audi brake servos and pressure regulators category.

Practical service and operational tips

During any intervention in the braking system, it is worth paying attention to the condition of the reservoir, the cap, and the surrounding area – any signs of leakage, dirt, or mechanical damage may indicate the need for replacement. The installation of the cap should be carried out on a clean reservoir edge, adhering to recommendations regarding tightening torque and working position.

For drivers who are simultaneously servicing other vehicle systems, the guide on selecting and maintaining comfort components may be helpful. More practical information can be found in the article Air conditioning and heating – part selection and maintenance for year-round comfort, where principles of working with used OEM components and good service practices are discussed.