The U.S. wants to forcibly limit how fast trucks, buses and other large vehicles can travel on the nation's highways. A new proposal Friday would impose a nationwide limit by electronically capping speeds with a device on newly made U.S. vehicles that weigh more than 26,000 pounds. Regulators are considering a cap of 60, 65 or 68 miles per hour, though that could change. The government said capping speeds for large vehicles will reduce the 1,115 fatal crashes involving heavy trucks each year and save $1 billion in fuel costs.