Nearly half of the trucks taken out of service during this year's 72-hour Roadcheck were cited for brake problems, according to the Commercial Vehicle Safety Alliance. Brake shortcomings were followed by deficient lights, tires and wheels, load securement and suspension. For all inspections, 76% of vehicles checked met mechanical safety standards with 24% taken out of service. This was a slight improvement from last year, when 26% were taken out of service during the annual roadside inspections.

About 62% of drivers who were taken out of service were cited for violations of hours-of-service rules, followed by driver's license infractions and driving while disqualified. More than 94% of all drivers met safety fitness standards, with just under 6% placed out of service, a slight improvement from last year.

In all, 42,795 trucks and buses were inspected June 5-7 throughout Canada, the U.S. and Mexico.