Mack DM Brake problems by year

On certain class 8 chassis built with hendrickson lift axles which contained webb brake drums, the brake drums could experience premature crack of the braking surface resulting in reduction or complete loss of braking on that wheel end or loss of brake drum...

Certain trucks fail to comply with the requirements of federal motor vehicle safety standard no. 121, "Air brake systems." The front brake chamber on some 18,000 lb. And 20,000 lb front axle assemblies is too small to meet stopping distance requirements.

Vehicle description: heavy duty trucks equipped with certain meritor-wabco brake system two and four port relay valves. The valve may stick open when a high-pressure application is released.

Vehicle description: heavy duty trucks built with bendix air abs with an ec-17 1030r electronic control unit (ecu), there have been reports of unwanted abs activation at low speeds caused by 1) chafed abs wheel speed sensor wires on rotating parts or 2) a...

Air system blockage in the air dryer occurs degrading the moisture removing capabilities of the dryer when the vehicle is operated in a cold environment and moisture accumulates and freezes in the air dryer or in the line between the dryer and the air system...

Delays of up to about 2 seconds may exist in the brake application times to the brakes on the bogie axles in the presence of certain types of wheel speed sensor signal discontinuities or distortions that may occur as a result of sensor wire failure. This...

An axle "no brake" condition could result from an eaton controller internal electrical malfunction. This condition may cause the anti-wheel lock valve solenoid to be continuously energized and prevent the brakes from being applied on one of the axles. As a...