Pr Number Allocation - Brakes
The following tables explain the PR numbers. These are important for the brake caliper/brake rotor and brake pad combination.
| Brake System | ||||
| Dual-Circuit Brake System With Diagonal Distribution And ABS, EBV, EDL, ASR, ESP, ECD And EPB |
| Front Brakes PR- 1LA, 1LB, 1LD, 1LJ, 1LT 1ZT | ||||
|---|---|---|---|---|
| Production-relevant number (PR number) | 1LT 1LY | 1LA, 1LB | S-4 / S5+1LJ, 1LD 1ZT | |
| Brake Caliper | FN3 16" | FBC 16" | FBC 17" | |
| Brake rotor, ventilated | Diameter in mm | 314 | 320 | 345 |
| Brake rotor, thickness | mm | 25 | 30 | 30 |
| Brake rotor, wear limit | mm | 23 | 28 | 28 |
| Pad thickness with backing plate and dampening sheet | mm | 20.3 | 20.3 | 20.3 |
| Brake pad wear limit with backing plate and dampening sheet | mm | 10 | 10 | 10 |
Maximum Lateral Run-Out Of Steel Brake Rotor = 0.06 mm
Measurement In Installed Brake Rotor
Dial Indicator Bracket:VAS6079/1 - Dial Indicator - 0-10mm:VAS6079
Clean Dirt And Rust Off The Brake Rotor.
Measure 10 mm Away From The Outer Edge Of The Brake Rotor.
| Front Brakes PR- 1LM / 1ZL | ||
|---|---|---|
| Brake rotor, ventilated | Diameter in mm | 365 |
| Brake rotor, thickness | mm | 34 |
| Brake rotor, wear limit | mm | 32 |
| 8-piston brake caliper, Brembo | Diameter in mm | 32 / 28 |
Maximum Lateral Run-Out Of Steel Brake Rotor = 0.06 mm
Measurement In Installed Brake Rotor
Use Dial Indicator Bracket:VAS6079/1 - Dial Indicator - 0-10mm:VAS6079
Clean Dirt And Rust Off The Brake Rotor.
Measure 10 mm away from the outer edge of the brake rotor.
Hairline cracks on the brake rotor friction surface are often noticed during brake repairs. Hairline cracks up to 10 mm long are not a technical flaw and do not justify a brake rotor replacement.
Brake rotors with friction surfaces that have worn through should be replaced.
| Ceramic Front Brakes, PR- 1LW | ||
|---|---|---|
| Brake Caliper | Brembo | |
| Brake rotor, ventilated | Diameter in mm | 380 |
| Brake rotor, thickness | mm | 38 |
| Brake rotor, wear limit | The wear value is the minimum brake rotor thickness during manufacturing and is stamped into the brake rotor cup. | |
| Brake caliper, 6 piston monoblock | Diameter in mm | 2 x 32/ 36/ 38 |
| Minimum pad thickness with backing plate and dampening sheet | mm | 9.5 |
Depending on the version, the minimum brake rotor weight is stamped on. The brake rotor must be weighed to further evaluate the wear. If the minimum weight has been reached, the brake rotor must be replaced. Always replace brake rotors in pairs on each axle.
Hairline cracks on the friction surface of ceramic brakes occur during the manufacturing process and can be found on new brakes in different forms. Hairline cracks on the friction surfaces are not a reason to replace the ceramic brake rotors.
For these models, the ceramic brakes are only installed in the front.
| Rear Brakes PR- 1KW, 1KE, 1KP, 2EH | |||
|---|---|---|---|
| Production-relevant number (PR number) | 1KW, 2EH | S4 / S5+1KE, 1KP | |
| Brake Caliper | CII-43 EPB (16") | CII-43 EPB (17") | |
| Brake Rotor | Diameter in mm | 300 | 330 |
| Unvented brake rotor thickness | mm | 12 | --- |
| Internally vented brake rotor thickness | --- | 22 | |
| Brake rotor, wear limit | mm | 10 | 20 |
| Pad thickness with backing plate and dampening sheet | mm | 17.5 | 17.5 |
Maximum Lateral Run-Out Of Steel Brake Rotor = 0.06 mm
Measurement In Installed Brake Rotor
Dial Indicator Bracket:VAS6079/1 - Dial Indicator - 0-10mm:VAS6079
Clean Dirt And Rust Off The Brake Rotor.
Measure 10 Mm Away From The Outer Edge Of The Brake Rotor.
| Rear Brakes PR- GP0, GP1 GP2 1KZ | |||
|---|---|---|---|
| Production-relevant number (PR number) | GP0, GP1 | GP2 2ED 1KZ | |
| Brake Rotor | Diameter in mm | 330 | 330 |
| Brake rotor thickness | mm | 22 | 22 |
| Brake rotor, wear limit | mm | 20 | 20 |
Maximum Lateral Run-Out Of Steel Brake Rotor = 0.06 mm
Measurement In Installed Brake Rotor
Dial Indicator Bracket:VAS6079/1 - Dial Indicator - 0-10mm:VAS6079
Clean Dirt And Rust Off The Brake Rotor.
Measure 10 mm Away From The Outer Edge Of The Brake Rotor.
The brake system installed in a vehicle is indicated on the vehicle data label by the relevant PR number -A and B-.
The 8T model type is shown here as an example.
- The brake system installed in a vehicle is indicated on the vehicle data label by the relevant PR number -A and B-.
- The 8K model type is shown here as an example.
Hairline cracks on the brake rotor friction surface are often noticed during brake repairs. Hairline cracks up to 10 mm long are not a technical flaw and do not justify a brake rotor replacement.
Brake rotors and brake pads that have a worn through friction surface should be replaced.