The Teamsters union claimed its first major victory under the leadership of James P. Hoffa with the ratification of a four-year contract with trucking companies that haul new cars to showrooms across the country. Under the terms, drivers who choose to retire after 25 years of work would get better pension benefits, including health insurance for those age 55 and older. Also, retirees over age 65 would get new prescription drug benefits to supplement government Medicare coverage.