A vehicle lift for use in conjunction with a vehicle to facilitate passengers boarding and leaving the vehicle. The vehicle lift has an improved driving mechanism for moving a platform between a stowed position to a deployed position. The driving mechanism includes a bidirectional motor which is mechanically coupled to a gear box which in turn is coupled to a pinion that is connected to a main sprocket. A longitudinal bracket is affixed to the underside of a top panel of the mounting enclosure and is located parallel to a longitudinal guide bar. At both ends of the longitudinal bracket are sprockets which are coupled by a loop chain. Accordingly, engaging the main sprocket with the loop chain moves the traveling assembly inward or outward with respect to the vehicle. The chain is immobilized by a manual spring biased locking mechanism to prevent the chain from moving linearly along the bracket. Therefore, when the motor is energized, it actuates the gear box which in turn drives the pinion, which in turn rotates the main sprocket to linearly travel on the chain moving the platform to a deployed position and visa verse.