Audi A1 S1 8X Brake Caliper Wheel Braking Unit Rear Left N/S 8X0615423B

Audi A1 S1 8X Brake Caliper Wheel Braking Unit Rear Left N/S is an original braking system component designed for installation on the rear axle on the driver's side. As part of the Brake Calipers and Brackets group, it ensures precise brake pad guidance and stable operation of the entire braking mechanism, which translates into predictable vehicle behavior during daily use.

Specifications and technical data

• SKU: 8X0615423B
• Mark: Audi
• Condition: Used
• OEM Part Number: 8X0615423B
• Substitutable numbers: 8X0615423B, 8X0 615 423 B
• Location on the vehicle: Rear, Left
• Part type: Brake Caliper
• Category: Calipers & Brackets

Purpose and vehicle placement

The presented caliper is designed specifically for installation on the rear left axle of Audi A1 / S1 8X generation models. The dedicated placement on the vehicle ensures correct mounting geometry, proper brake pad guidance, and correct cooperation with the brake disc and other system components.

Such a fit reduces the risk of installation problems, minimizes the need for modifications, and allows for maintaining factory brake performance parameters, which is particularly important in cars with a more dynamic character, such as the S1 version.

Original origin and benefits of using a used part

The caliper comes from the Audi brand offer, thanks to which it maintains factory manufacturing standards, dimensional compliance, and the operating characteristics intended by the manufacturer. The original design ensures proper body rigidity, even pad pressure, and stable operation over a long period of use.

As a used component, it represents a favorable compromise between repair costs and maintaining OEM quality. In many cases, using an original recycled caliper allows for cost savings compared to new replacements, while maintaining high precision and compatibility with the factory braking system.

Function in the braking system and technical aspects

The task of the rear left caliper is to convert brake fluid pressure into the clamping force of the pads against the disc, which directly affects braking efficiency and vehicle stability. A properly selected and functional caliper:

• ensures even pad wear on both sides of the axle,
• reduces the risk of the vehicle pulling during braking,
• maintains proper system operation (no excessive vibrations or noise),
• supports the correct operation of assistance systems such as ABS or ESP.

Thanks to the factory design tailored to the specific Audi 8X platform, the caliper works with the equipment intended by the manufacturer – discs, pads, and brake lines – which facilitates service and subsequent operation.

Application in service practice

This rear left brake caliper will work well both for standard replacement of a worn element and for post-accident repairs or restoring the car to factory condition. Choosing an original Audi component facilitates the mechanic's work, shortens installation time, and reduces the risk of fitment problems that may occur with some replacements.

In workshop practice, the dimensional repeatability and predictable behavior of OEM calipers are particularly appreciated, which translates into stable system pressure, correct piston return, and even brake operation across the entire axle.

Braking system expansion and technical knowledge

If you are planning a comprehensive repair or upgrade of the braking zone in your Audi and need other elements from the same group, such as additional calipers, brackets, or mounting elements, check the available parts in the Audi Brake Calipers and Brackets category.

To better understand how to safely use original, used braking system components and how to optimally reduce service costs, it is worth checking out our guide: Brake calipers under the microscope: How to effectively reduce braking system repair costs by choosing proven recycled parts.