Abstract: A truck assembly for a skateboard includes an axle housing, a base, and a kingpin connecting the axle housing and base. The kingpin holds the axle housing and a base surface of the base a predetermined distance apart. The truck further includes a turning mechanism between the axle housing and base, around the kingpin. The turning mechanism includes opposed cam surfaces that are angled along the axis of the kingpin and an elastomeric bushing so that rotating the axle housing about the kingpin pushes the cam surfaces apart, against the compression pressure of the elastomeric bushing. The truck assembly additionally includes an adjustment mechanism for adjusting the pressure against the bushing. The adjustment mechanism includes an adjustment surface on the base of the truck assembly with two or more adjustment points, each a different distance from the base surface along the direction of the kingpin. An adjustment ring surrounds the kingpin, between the base surface and the turning mechanism.