Brake discs

General Information

The condition of the brake discs is critical to braking performance. Factors such as runout, corrosion and variations in thickness will cause vibrations and pulling.

For this reason, the discs should always be inspected when replacing the pads. See specifications Specifications regarding thickness and maximum runout.

Machining of brake discs

Inspect the discs for signs of damage. The disc must be replaced if it is cracked or worn to the extent that there is no margin for machining. In the case of radial scoring, uneven wear, corrosion deposits etc., tests have shown that machining the disc on the car with a special machining unit is a fully satisfactory alternative to replacement in terms of tolerance and surface finish.

If machining a disc:

If the disc must be removed to clean the ABS sensor and sensor wheel, or for any other reason, this should be carried out prior to machining (see below).

Mark the position of the disc with respect to the hub. Remove the disc and clean the sensor and sensor wheel with a soft brush (a steel brush must not be used). Clean the mating surfaces on the disc and hub thoroughly. Mount the disc on the hub in accordance with the marking.

Machining

The machining procedure is described in the instructions supplied with the machining unit.