Problems with RV slide-outs include failure of mechanical gears and electrical parts, loss of motor power, hardware cracks and rubber seal damage. Electric slide-out motors are likely to break when amperage becomes excessive, and drive pins shear. Pump and valve failure is a problem for hydraulic systems.
RV slide-outs depend on either an electronic system or a hydraulic system, and both systems are prone to various problems due to wear and tear. Electrical slide-outs are usually more lightweight and smaller in size, but they are problematic when not properly integrated into the RV coach. Main problems for these systems are failing motors, malfunctioning gearbox and drive pins inside of the main gear mechanism wearing down. The electrical relays to the motor can trip or break after being hit with too much resistance inside the slide-out unit.
Slide-outs running on hydraulic systems shut down after hydraulic fluid lines rupture from friction and heat. Hydraulic lines are prone to connection problems due to leaking. Stability of slide-out units are always a concern, because they must remain level while extending outwards or retracting. An improperly sealed slide-out may cause floor damage. Rubber seals must be kept lubricated to avoid cracking and stiffness, which leads to water damage. Manual cranks are essential for retracting stuck slide-outs.