Current federal law limits trucks with five axles to 80,000 during normal circumstances. A push to increase freight truck weights to 97,000 pounds with six axles in the transportation bill was defeated before the measure was signed into law.
The hours of service rules for truckers were adopted in December after a vigorous battle between safety advocates and the trucking industry.
The rules, which were implemented by the Federal Motor Carrier Safety Association, limit the number of hours a driver could work to 70 per week.
Under the old rules, truckers could drive 82 hours per week.
Safety advocates had pushed transportation officials to also place a limit on the number of hours truckers could drive each day. However, the new rules require truckers to take a break of at least 30 minutes for every eight hours they drive, but they maintain a daily 11-hour limit on driving.