Audi Q3 8U Rear Brake Caliper Wheel Braking Unit Left N/S 8U0615403B

Audi Q3 8U Rear Brake Caliper Wheel Braking Unit Left N/S is an original braking system component from the Brake calipers and brackets group, designed for installation on the rear left axle of the vehicle. Thanks to its factory origin, it ensures a perfect fit for the brake design of the Audi Q3 8U generation, which translates into stable performance and predictable vehicle behavior during braking. This is a practical solution for users looking for parts with known installation specifications.

Specifications and technical data

• SKU: 8U0615403B
• Mark: Audi
• Condition: Used
• OEM Part Number: 8U0615403B
• Substitutable numbers: 8U0615403B, 8U0 615 403 B
• Location on the vehicle: Rear, Left
• Category: Calipers & Brackets

Purpose and vehicle placement

The presented caliper is designed to operate in the rear part of the braking system, on the left side. Such placement requires an appropriate body shape, correct brake pad guidance, and compatibility with the hub and brake disc geometry of the Audi Q3 8U. Using a dedicated caliper reduces the risk of installation issues, leaks, or uneven brake pad pressure.

The component belongs to the Brake calipers and brackets group, which means it works directly with the brake disc, pads, and brake lines, responsible for converting brake fluid pressure into the clamping force of the pads against the disc.

Technical and functional characteristics

As an original Audi component, the caliper has been designed to maintain the factory performance parameters of the braking system. The appropriate design of the guides, piston, and mounting seats allows for:

• correct positioning of the pads relative to the disc,
• stable, repeatable pressure during braking,
• compatibility with factory mounting hardware and brake lines,
• maintaining the proper geometry of the rear axle braking system.

This ensures consistent operation of the entire system, which is important for both braking efficiency and even wear of the pads and discs.

Component condition and installation aspects

The offered caliper is a used part, which allows for an economical repair of the braking system while maintaining the original design. Before installation, a standard service procedure is recommended, including inspection of working surfaces, seals, and the freedom of movement of the guides, in accordance with the vehicle manufacturer's guidelines and good workshop practices.

Selecting the correct caliper for the Audi Q3 8U should take into account compatibility with the body version and braking system configuration. In case of doubt, it is worth comparing the mounting geometry and the type of brake line connection with the part removed from the vehicle.

Safety and braking system operation

A correctly selected and installed caliper on the rear left axle affects vehicle stability during braking, especially in emergency situations and when activating assistance systems such as ABS or ESP. Regular inspection of the condition of calipers, pads, and brake discs helps reduce the risk of overheating, uneven wear, and a decrease in braking efficiency.

If you want to better prepare for choosing used braking system components, you will find practical tips in the article: Second-hand braking system: how to safely choose discs, calipers, and ABS?. This is a helpful source of knowledge when planning repairs using used parts.

Expanding Audi braking system upgrades

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 additional calipers, brackets, or mounting holders, check out the available parts in the Audi brake calipers and brackets category.

When deciding between used or new parts, a guide comparing both solutions may also be helpful: Car parts – new or used? We compare costs, quality, and durability. This will make it easier to match your repair strategy to your budget and operational expectations.