Question Most heavy trucks with manual transmissions require ____ to change gears. Answers Single clutching Double clutching Triple clutching Explanation Most heavy vehicles with manual transmissions require double clutching to shift gears. Learning to effectively change gears by double clutching takes practice. Take a FREE Practice Test Now This questions appears in the following tests: California Knowledge Test Class A , Missouri Knowledge Test Class A , North Carolina Knowledge Test Class A , Vermont Knowledge Test Class A , Alaska Knowledge Test Class B , Oklahoma Knowledge Test Class B , Rhode Island Double , Hawaii Tank ,