All motor homes I have seen have a way to manually move a slide in and out if the drive motor fails. The biggest challenge to this is locating where it is and disengaging the motor. On the front slides the motor is usually located in the storage compartment under the slide. On the rear slides the motor is usually located under the bed. On my front slide I can use a pipe wrench or a large cresent wrench to move the slide in or out. On the rear slide I can use a 1/2" socket wrench.
Joe & Angie
Shih Tzu's Cookie & Rocky
2001 Tradewinds 7390 2011 CRV EX-L Navi w/ RoadMaster FuseMaster