NHTSA recall 78V210000
Service brakes, air › Antilock › Interconnecting assembly(wiring)
Mack DM and 13 more
Reported Oct 3, 197819,370 vehicles affectedMACK TRUCKS, INCORPORATEDBuilt Oct 1, 1977 – Sep 1, 1978
The defect
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 constitutes a non-compliance to federal motor vehicle safety standard no. 121, "air brake systems".
The remedy
Dealer will install new wheel speed sensors that incorporate improved wiring and the present bogie anti-wheel lock system will be changed to an axle-to-axle system for improved reliability.