Quick Answer
When your RV slide out motor runs but won't retract, it's typically a hydraulic system issue like low fluid, air in lines, or a faulty valve. Cable systems may have broken cables or stripped gears.
Tools & Parts Needed
Find these on Amazon: ATF Type F Hydraulic Fluid , Socket Wrench Set , LED Work Light
The Problem
When your slide out motor runs but doesn't retract, you likely have a hydraulic system since cable-driven slides usually make grinding noises when they fail. The most common causes are low hydraulic fluid, air in the lines, or a stuck retraction valve.
Why This Happens
Start by checking fluid levels and looking for leaks around the slide mechanism.
Hydraulic Systems
Low fluid: Add manufacturer-specified hydraulic fluid (often ATF Type A or Dexron III). Run system to circulate and check level again.
Air in lines: Cycle the slide out and in several times to purge air. You may hear gurgling sounds initially.
Stuck retract valve: Try tapping the valve body gently with a wrench handle while operating the switch. If this works temporarily, the valve needs replacement.
Worn seals: If cylinders leak fluid, internal seals may be worn. This requires professional cylinder rebuild or replacement.
Cable Systems
Broken cable: Inspect cables for fraying or breaks. Broken cables usually cause loud noises when the motor runs.
Stripped gears: If you hear grinding, the drive gears may be stripped. This requires gearbox disassembly.
The Solution
You'll need:
- Hydraulic fluid (ATF Type A, Dexron III, or manufacturer-specified)
- Socket wrench set
- Flashlight or work light
- Safety glasses
- Work gloves
- Jack stands or leveling blocks
- Funnel
- Clean rags
Follow these steps:
- Safety first: Ensure RV is level and stable. Never work under a partially extended slide without proper support.
- Identify your system: Look under the slide for hydraulic cylinders (round tubes) or cable mechanisms (pulleys and cables). Most modern RVs use hydraulic systems.
- Check hydraulic fluid level: Locate the hydraulic pump (usually near the slide mechanism). Check the reservoir - it should be between MIN and MAX lines when slide is retracted.
- Inspect for leaks: Look around cylinders, fittings, and hoses for wet spots or puddles. Hydraulic fluid is typically red and slippery.
- Test the retract valve: Try retracting the slide. Listen for valve clicks near the pump. No clicking may indicate a stuck valve.
- Check electrical connections: Ensure all wiring to the pump motor and valves is secure and corrosion-free.
- Manual override test: Most systems have a manual valve for emergency retraction. Consult your owner's manual for location.
Situations That Need a Professional
Contact an RV service center if you encounter:
- Hydraulic fluid leaking from cylinders
- Broken or frayed cables in cable systems
- Electrical issues with the pump motor
- Slide is stuck and manual override doesn't work
- You're uncomfortable working with hydraulic systems
- Multiple attempts at bleeding air haven't resolved the issue
Important: Never attempt to force a slide in with excessive pressure or improvised tools, as this can cause expensive structural damage.
Preventive Measures
Maintain your slide out system with these practices:
- Check hydraulic fluid levels monthly during camping season
- Lubricate slide rails and seals every 3 months with manufacturer-recommended lubricant
- Cycle slides monthly even when not in use to keep seals lubricated
- Keep slide rails clean and free of debris
- Inspect cables and pulleys annually on cable systems
- Have hydraulic systems professionally serviced every 2-3 years
- Never operate slides when RV is not level
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