One problem related to brake master cylinder has been reported for the 2000 Mercedes Benz M Class. The most recently reported issues are listed below.
2000 ml-class mercedes ml55 leaking brake line due to chaffing as described in your investigation of 52,000 ml-class mercedes SUV's. The brake line running from the master cylinder to the abs pump suffers eventual failure due to chaffing against a poorly positioned fuel line. Suffered near total failure of braking system this morning due to this issue. I have all parts removed, and a failure assessment provided by the service technician. The work was not performed at a Mercedes Benz dealer, thereby ensuring objectivity of the diagnosis.