Audi RS6 C7 Brake Caliper Wheel Braking Unit Rear Left N/S 4G0615403C

Audi RS6 C7 Brake Caliper Wheel Braking Unit Rear Left N/S is an original component from the Brake calipers and brackets group, designed to operate within the demanding braking system of this sports sedan. This used component ensures factory-standard geometry, proper brake pad guidance, and stable interaction with the brake disc, which translates into predictable and safe braking of the rear axle.

Specifications and technical data

• SKU: 4G0615403C
• Mark: Audi
• Condition: Used
• OEM Part Number: 4G0615403C
• Substitutable numbers: 4G0615403C, 4G0 615 403 C
• Location on the vehicle: Rear, Left
• Category: Calipers & Brackets

Purpose and vehicle placement

The presented caliper is designed for installation on the rear left side of the vehicle. It is responsible for evenly pressing the brake pads against the disc, stabilizing the operation of the entire rear axle during emergency braking, high-speed driving, and while electronic stability control systems are active.

Precise placement on the vehicle reduces the risk of errors when selecting parts and facilitates service planning – especially when replacing a single caliper or a pair on the axle.

Technical and functional characteristics

As an original Audi brand component, the caliper is structurally matched to the factory braking system of the RS6 C7. This means correct mounting spacing, appropriate piston working volume, and compatibility with the brake discs and pads specified by the manufacturer.

This solution ensures:

• stable transfer of pressure from the hydraulic system to the brake pads,
• repeatable braking force after the system warms up,
• proper cooperation with safety systems (ESP, traction control, ABS),
• maintenance of the factory braking balance between the front and rear of the vehicle.

Condition, origin, and advantages of using a used part

The item is offered as used, which in practice means it comes from disassembly and retains the manufacturer's original specifications. For advanced models such as the RS6 C7, using parts from the same production line often allows for better maintenance of the entire braking system's consistency than many aftermarket replacements.

Choosing a used caliper is a cost-effective and technically safe solution, provided that the installation is performed in accordance with service procedures – including brake fluid replacement, system bleeding, and inspection of other components on the axle.

Selection, installation, and compatibility

Before installation, it is recommended to verify compatibility with the vehicle based on the OEM part number and available interchangeable numbers. This minimizes the risk of mismatch, especially in equipment versions that differ in disc diameter or braking system configuration.

During replacement, it is worth:

• checking the condition of the disc and pads on the rear left side and on the opposite side of the axle,
• assessing the condition of brake lines and mounting points,
• performing a road test with a braking efficiency measurement after installation.

Technical support and additional materials

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 selecting a used brake caliper, assessing the technical condition and compatibility with the vehicle's system is particularly important – you can find practical tips, a checklist, and common purchase mistakes in the article Second-hand braking system: how to safely choose discs, calipers, and ABS?.