Fault assessment of brake discs
With few exceptions, disc brakes are used as wheel brakes on the front axle of passenger cars. Depending on the load, disc or drum brakes are used on the rear axle. The following remarks are limited to the disc brake.
Analysis shows that a large proportion of customer complaints about faulty brake systems are attributed to the brake disc. And in those cases, in turn, brake judder is the main cause for complaint. Because of the complexity described above and the numerous possible influencing factors, brake disc damage and its causes are often difficult to identify in any particular case. Experience has shown that, in most cases of actual brake disc damage, the root cause usually lies elsewhere (excessive disc run-out due to overall tolerances, unsuitable brake pads, faulty wheel brakes, etc.). In many cases, the brake discs about which a complaint has been received, prove to be in perfect working condition and the root causes of deficiencies have not been identified. This inevitably leads to complaints being rejected after costly and time-consuming tests, much to the annoyance of all parties concerned. Even if the immediate problem seems to be solved by a replacement of certain parts, the symptoms usually reappear after a while. This situation can be improved – and customer satisfaction guaranteed – only if the root causes can be reliably determined and only if approved spare parts are used and maintenance jobs are carried out with care and precision.