If your trailer is anything like my Forest River Cardinal you'll find a hydraulic pump and reservoir underneath near the front. On the end of the hydraulic motor you should find a cover the pops off. You can insert a standard hex bit powered by a cordless drill. Easy as that...forward or reverse depending on which way you want the slides to go. I doubt you'l need to worry about though. Those hydraulic systems are pretty durable. Ours gets a ton of use and we've had no problems.
2000 Ford F-350, AT, DIY intake, 4" turbo back exhaust, triple gauge pod, sonnax/tricumulator, aftermarket diff. cover.
2005 31' Forest River Cardinal and Honda EU2000