Abstract: A pickup truck cab and box marrying and decking system for vehicle assembly plants is adapted to newer style pickup trucks in which portions of the box front end extend forwardly to wrap around the back corners of the cab to provide a flowing appearance. The disclosed system lifts the cab and box sections off skids on a first conveyor and transfers them to over a second conveyor bringing in a chassis frame. Measurement devices determine the position of locating fixtures on the frame. The cab and box sections are then brought together, or married, and are precisely aligned with the frame locating fixtures. The cab and box sections are then lowered to deck the married sections on the frame in precise alignment with the locating fixtures.

Abstract: A weight bearing trolley moves along a track having flanges between which a guide wheel of said trolley is positioned. The movement of the trolley is monitored to determine when braking is desired and, when desired, pressure is applied to said guide wheel, forcing it into contact with one of said flanges and producing frictional retarding force braking said trolley. A fail-safe actuator utilizes fluid pressure to keep a brake operating spring compressed when braking is not wanted.