Are antilocks required on big truck rigs?
In March 1995, the National Highway Traffic Safety Administration issued a rule requiring antilock brakes for heavy trucks, tractors, trailers, and buses. All new truck tractors were required to have antilocks after March 1, 1997, and they were mandatory on new air-braked trailers and single-unit trucks and buses after March 1, 1998. New single-unit trucks and buses with hydraulic brakes had to be equipped with antilocks after March 1, 1999. This is not the first antilock standard for U.S. trucks. A federal brake standard took effect in 1975, but its antilock and stopping distance requirements were suspended after litigation in 1978. Antilock brake systems have been required on all new trucks, buses, and trailers in Japan and the European Union for several years. Antilocks are important for big trucks because of the poor braking capabilities of these vehicles compared with passenger cars. On dry roads, big trucks take much farther to stop — 47 percent farther in Institute tests. On wet
