Abstract: A control circuit is provided for controlling the operation of the solenoid of an air powered actuator which is utilized for retracting the locking pins of a slider used for the adjustment of the suspension of a vehicle longitudinally with respect to the body of the vehicle. The control circuit is operatively connected to the trailer marker light circuit, the service brake light circuit and must be actuated a predetermined number of times within a predetermined length of time, after the service brake light circuit has been actuated for a predetermined length of time, to allow the air powered actuator to be actuated.

Abstract: A control circuit is provided for controlling the operation of the solenoid of an air powered actuator which is utilized for retracting the locking pins of a slider used for the adjustment of the suspension of a vehicle longitudinally with respect to the body of the vehicle. The control circuit is operatively connected to the trailer marker lights circuit and must be actuated a predetermined number of times within a predetermined length of time to allow the air powered actuator to be actuated.

Abstract: A safety switch and delay switch is provided for an air powered actuator which is utilized for retracting the locking pins of a slider which is used for the adjustment of the suspension of a vehicle longitudinally with respect to the body of the vehicle. The safety switch prevents the air powered actuator from being operated unless the trailer emergency brake is in its set and locked position. The delay switch prevents the inadvertent actuation of the air powered actuator when the truck brake is momentarily actuated.

Abstract: A mounting bracket for mounting an air powered actuator for retracting the locking pins of a slider comprising a vertically disposed central position having first and second support arms extending therefrom for attachment to spaced-apart frame members of the slider frame. A horizontally disposed tube is secured to the upper end of the central portion of the mounting bracket and has an elongated rod removably received thereby. One end of the elongated rod extends through one of the frame members, while the other end of the elongated rod extends through the other of the frame members.