Abstract: An improved electric tongue jack with one or more memory buttons to retract or extend to a predetermined desired height. A first memory button is provided to engage in a memorizing operation to store a desired actual height of the hitch. When the first memory button is subsequently engaged, the motor gear assembly is controlled to return the hitch to the desired height. A second memory button is used as an automatic retraction for the jack leg once the trailer has been set on the hitch ball/tow vehicle. Once the auto retract location has been set, the user may push the auto retract button once and the leg will automatically retract to the preset height. The memory buttons are controlled by software in a printed circuit board inside the head of the jack.

Abstract: An improved device and method of lubrication for a tongue jack, 5th wheel jack, or other jack or other threaded positioning device. Ports are provided in the inner and outer tubes of the jack. The aligned ports provide access to a lubrication cavity in the jacknut. The lubrication cavity may include a grease fitting such as a zerk fitting. When the ports are in alignment, a grease gun can be inserted easily to the zerk fitting to apply grease to the interior structure of the nut as well as to the threads of the jackscrew. The lubricant may be introduced directly at a region of contact between a screw and the load bearing element. Applicant's test results show that this improved lubrication can increase the life cycle of the jack by more than 100%.

Abstract: A tire chock with improved ease of use and prevention of theft. A threaded rod expands a scissor frame to force foot plates against a tire. The scissor frame foot plates are pulled apart or pushed together so that the frame fits between the tires. A hand-adjustable, freely rotatable nut is on the lower end of the rod is tightened. A wrench is used to tighten a second nut on the upper end of the rod, and a lock member is secured over the second nut.