Code of Alabama
Article 3 - Operation and Use of Vehicles Generally.
Section 32-5A-57 - Coasting Prohibited.

(a) The driver of any motor vehicle when traveling upon a down grade shall not coast with the gears or transmission of such vehicle in neutral or the clutch disengaged.
(b) The driver of a truck or bus when traveling upon a down grade shall not coast with the clutch disengaged.