Compare popular RV floorplans with and without slide-outs, and the advantage of having slides is clear: they create robust interior living space when extended without extending the RV’s length. We’ll cover the basics here if you’ve ever wondered how RV slide-outs work.
What Are Common RV Slide-Out Mechanism Types?
There are three main power RV slide-out types: through-frame, cable-driven, and above-floor. Others exist, like manual hand-crank and push-by-hand RV slide-outs, but these are far less common among new campers. Depending on the slide-out sizes and required weight capacities, some RVs will use multiple slide-out mechanisms if they have more than one slide.
For example, you might find a large fifth wheel with two living room slides and a bedroom slide. Depending on engineering considerations, the manufacturer may decide to use a worm gear slide in the bedroom, a cable-driven slide in the kitchen, and a rack-and-pinion slide in the living area.
Your owner’s manual is your best resource for determining which slide-out mechanism(s) your RV uses.
Technician Tip: Note that some manufacturers refer to worm gear slide-outs under the “Schwintek” brand name, and some call rack-and-pinion slides “electric through-frame” slide-outs.
How Does an RV Slide Out Work?
Each slide-out type operates a little differently, so let’s break down those three main types:
Through-Frame
Through-frame slides with electric worm or screw drive are often used for smaller slide-outs in RV bedrooms or wardrobes. Hydraulic cylinders are often used to drive through-frame slide-outs that are larger or need to support more weight. These designs rely on one or multiple actuator motors or a hydraulic pump and fluid (stored in a reservoir) to power extension and retraction. In most cases, the motor(s) or pump are wired to a three-way switch (OFF, EXTEND, and RETRACT) on your RV’s interior control panel, where you control the operator.
Cable-Driven
Cable-driven systems are typically used for deeper, larger slides that support the weight of RV furniture. This type of RV slide-out is constructed with steel cables on all four corners. When the slide room is extended, these cables are visible on the slide’s exterior. Above the slide-out room, the cables are connected to a 12V actuator motor responsible for extension and retraction. This motor is wired to your RV’s wall-mounted control panel, allowing you to use a three-way switch to open and close your slide-out as desired.
Above-Floor
Above-floor slides include rack-and-pinion or worm drive designs that rely on one or multiple actuator motors to control extension and retraction. These motors can be mounted on sidewalls, under the slide room, or on top of the slide room. With larger slides, multiple motors work in tandem to control synchronous operation. A control panel inside the RV operates the extension and retraction function, but you’ll also typically find an exterior control box mounted in an underneath compartment.
Should You Leave RV Slides In or Out?
RV slide-outs should remain retracted when your RV is in storage and when you’re traveling. Keeping your slides in when you’re not using your RV reduces strain on the frame and eliminates environmental exposure to the slide roof or slide topper.
When camping for a long time, leaving your slide rooms extended is fine. Just check the slide roof for debris or obstructions during campsite breakdown to ensure nothing can damage or restrict movement before retracting the slide for travel. This is why many RVs come with slide-out toppers and why many RVers install them if the manufacturer doesn’t offer them as a factory-built feature.
Technician Tip: NEVER leave your RV slide partially extended or retracted. It should be fully extended in camp and fully retracted for travel or storage.
How Long Can You Leave RV Slides Out?
There’s no steadfast rule for how long you can leave an RV slide-out extended. However, regular extension and retraction can be beneficial for the slide-out mechanism to remain well-lubricated. Additionally, some RVers use slide-out supports to provide relief for the structural frame supporting the slide-out’s weight.
Before you purchase slide-out supports, know they must be used carefully to avoid damaging the slide-out. Learn more about the process of using RV slide-out supports. But the key takeaway is that slide-out supports are best for full-time RV living in a single location. Their use must be prefaced with properly supporting your RV’s frame with jack stands to avoid sidewall damage.
How Much Weight Can an RV Slide Out Hold?
Slide-out weight capacity can differ by RV manufacturer, but RV slide-outs can hold anywhere from 600 to 2,500 pounds. Most fall in a mid-range from 1,400 to 1,500 pounds, but there are smaller bedroom slides with minimal weight capacity contrasted by full-wall slides that require a more sturdy design to support heavier appliances like an RV refrigerator, cooktop and oven, and even a washer and dryer if the RV is prepped for those.
Technician Tip: Slide-outs shouldn’t be used to store gear. Slide room floors are only fully supported when they are fully extended. Slide rooms should never be moved with people in them.
How Often Do RV Slide-Outs Fail?
RV slide-out failure rates depend on design, size, construction standards, and, most importantly, the degree and frequency of proper maintenance undertaken by the RV owner or a certified RV technician. The more you stay on top of seasonal and annual slide-out maintenance, the less likely it is to fail.
Here are some examples of seasonal and annual slide-out maintenance services:
Seasonal/Routine Slide-out Maintenance
- Inspect the roof and sides before retracting
- Inspect slide toppers
- Inspect trim and moldings
- Check for leaks
- Verify alignment in open and closed positions
- Check for soft spots in the corners of the roof and floor of the slide room
Annual Slide-out Maintenance
- Lubricate slide arms as directed by the manufacturer (rack and pinion)
- Sync actuator motors (above floor)
- Inspect receptacles and electrical connections (all types)
- Inspect the condition of any water, plumbing, and propane lines running under the slide (all types)
Technician Tip: If your slide mechanism fails with your slide extended, use one of these methods for manual slide out operation. Those methods are meant for retracting only! Once your slide is closed, proceed to a service center near you for a slide-out diagnostic.
Now that you know the basics of RV slide-out operation, here are a few more helpful resources:
What did you want to know about how RV slide-outs work that we didn’t cover? Ask in the comments below!
