00 - General, Technical Data: Brakes
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Vehicles with front and rear disc brakes
| Brake system | ||
|---|---|---|
| Dual-circuit brake system with diagonal distribution. ABS Bosch 5.7 or ABS Bosch 8.0 with Electronic Brake Distribution (EBD)/ESP Brake booster operating with manifold vacuum or vacuum pump |
| Brake master cylinder | Dia. mm | 25.4 | 26.99 |
| Brake booster, vacuum | Dia. in inches | 8" and 9" tandem | 8" and 9" tandem/Dual Rate |
| Assist factor | i | 5.5 | 5.5/12 |
| Front brakes | |||||||
| Brake caliper | C 54 | FN 3 | FN 3 | FNR-G 60 | FNR-G 60 | Brembo | |
| Disc size (inches) | 15 | 15 | 16 | 16 | 17 | 18 | |
| Production relevant no. | Pr.- No. | 1LZ | 1LB/1LE | 1LT/1LF | 1LA/1LD | 1LJ | 1LP |
| Front brake caliper, piston diameter | mm | 54 | 57 | 57 | 60 | 60 | 28/32 |
| Front brake disc | mm | 280 | 288 | 312 | 320 | 345 | 365 |
| Brake disc thickness, internally ventilated; | mm | 22 | 25 | 25 | 30 | 30 | 34 |
| Brake disc wear limit | mm | 20 | 23 | 23 | 28 | 28 | 32 |
| Pad thickness, with backing plate and dampening sheet | mm | 19.3 | 20.3 | 20.3 | 20.3 | 20.3 | - |
Brake discs
NOTE:
- Hairline cracks on brake disc friction surfaces are often observed during brake repairs. Hairline cracks up to 10 mm long are not a technical flaw and are not cause for brake disc replacement.
- Brake discs with friction surfaces that have worn through should be replaced.
| Rear brakes | ||||||
| Rear brake caliper | C38 | C38 | C41 | C43 | C43 | |
| Disc size (inches) | 15 | 16 | 16 | 16 | 18 | |
| Production relevant no. | Pr.- No. | 1KD | 1KP | 1KW | 1KE | 1KY |
| Rear brake caliper, piston diameter | mm | 38 | 38 | 41 | 43 | 43 |
| Brake disc | mm | 245 | 255 | 288 | 300 | 335 |
| Brake disc thickness | mm | 10 | 12 | 12 | 22 | 22 |
| Brake disc wear limit | mm | 8 | 10 | 10 | 20 | 20 |
| Brake pad, thickness with backing plate | mm | 16 | 16 | 16 | 17.5 | - |
| Brake pad wear limit with backing plate | mm | 7 | 7 | 7 | 8 | - |