Front Disc Brake: Introduction

WARNING: This page is about a different car, the 2011 Jaguar XKR, 2011 Jaguar XK, 2010 Jaguar XKR, and 2010 Jaguar XK. However, it is still accessible from the selected car via links, so may be relevant.

The front braking system features ventilated brake discs with single (naturally aspirated vehicles) or dual (supercharger (SC) vehicles) piston sliding calipers. On naturally aspirated vehicles the discs are 355 mm (13.98 in.) diameter x 32 mm (1.26 in.) thick. On supercharger (SC) vehicles the discs are 380 mm (14.96 in.) diameter x 36 mm (1.42 in.) thick.

The brake disc is manufactured from cast iron. The disc is retained on the wheel hub by two retaining washers and the wheel nuts.

Each caliper is mounted within a fixed carrier that is secured to the front wheel knuckle with two bolts. On supercharger (SC) vehicles the calipers are painted. Each outboard brake pad is installed with a pressed steel anti-rattle spring. On supercharger (SC) vehicles a badge is formed on the anti-rattle spring. The inboard brake pad of the left-hand (LH) brake incorporates a wear sensor.

NOTE: New pad wear sensor leads need to be fitted whenever the brake pads are changed irrespective of the brake pad warning sensor being triggered.

The brake pad wear sensor is wired in series with a wear sensor on the right-hand (RH) rear brake and the instrument cluster. If the thickness of one of the brake pads connected to a wear sensor decreases to a predetermined limit, the instrument cluster illuminates the brake warning indicator.