Checking the condition of the brake discs (Audi A4 B5)

If the front wheels are removed to check the brake linings, the condition of the brake discs is also checked at the same time.

There should be no deep grooves on the discs (due to dirt or too much worn pads). The grooves cut deeply into new brake linings, which significantly reduces their service life and reduces the braking effect.

Scratched brake discs can be ground on a lathe if they have not yet worn down to the minimum acceptable size over a long period of service.

Discs that are too thin are replaced in pairs.

The bluish tint of the brake disc does not matter.

Brake disc sizes

Brake discs	Not ventilated in front	Front with internal ventilation	Behind
Thickness of new Minimum thickness	15 mm 13 mm	25 mm 23 mm	10 mm 8 mm