2. A visual assessment of the residual thickness of the friction linings can be made through the viewing window provided in the caliper housing. Using a steel ruler, measure the thickness of the linings together with the metal substrates. Compare the measurement results with the requirements Specifications.
3. Assessing the thickness of the pads through the inspection window of the caliper gives only an approximate idea of the degree of wear of the friction linings. For a more detailed examination, the pads should be removed and thoroughly cleaned. At the same time, the correct functioning of the caliper and the condition of the brake disc can be checked (for more details, see Chapter Brake system).
4. If the wear of the friction lining of at least one of the pads is below the permissible limit, all four must be replaced (in the brake mechanisms of both front wheels). The procedure for replacing the pads is also described in Chapter Brake system.
5. Finally, reinstall the wheels and lower the car to the ground.