A vehicle includes a chassis, a cab carried by the chassis, and a bed carried by the chassis. A dilator tip which is asymmetric over at least a part of its length gives the tip different flexure characteristics in different radial directions. The track identifier and frame count of a received adaptive audio frame is compared to the track identifier and frame count contained in the synchronization signal. The propulsion control valve is piloted on both ends by fluid pressure in the gripper assemblies.