The step operates on a simple, reversing worm gear jack screw. The step is problematic in that the slides get junk on them, and indeed gravel, sand and stones get between the step and the running board. It is a good idea to lower the step a few mm so thre is more clearance between the step and the running board. The step is mounted on a number of lengths of ready rod, and can be lowered by losing the nuts and lowering it, then retightening the nuts. Spraying off the step with a hose to cler the crap is a good idea. I have a hose bib plumbed by the step with a short hose and nozzle to do this.
Also, a disarm switch, (chronicled elsewhere in this forum) is a good idea, so that it doesn't open when it is covered with crap.
Icarus