Navistar International Corp. jumped the most this year after Volkswagen AG changed CEOs, a move that could portend further deal-making between the U.S. truck manufacturer and its second-biggest shareholder.

General Motors Co. and Fiat Chrysler Automobiles NV reported hefty sales declines for the big trucks they’re overhauling this year, a troubling sign for a lucrative segment that’s held up well as the broader U.S. auto market shrinks.

AutoNation Inc., the largest car-dealer group in the U.S., reached an agreement to maintain and help manage fleets for Waymo, the self-driving car unit of Alphabet Inc.