The vast majority of RVs sold today have at least one slideout. Those slideouts have two important characteristics which many RVers believe they need to correct.
First, those slides seem to magically hover over the ground without any support! Surely when you add weight to them the laws of physics come onto play and put great stress on the RV where the slide connects?
Second, by hanging out away from the RV, they make it less stable and cause it to bounce or roll more as people move about inside. Booo!
One solution to these issues that you may find at your local RV retailer is a slideout support, also called an RV slide-out stabilizer or “slide jack”. So what exactly are these slideout stabilizers and do you need them for your RV?
Slide out structural supports or “slide jacks” are an RV accessory designed to add additional support to a slideout when it is extended from the RV. As a general rule, these are not necessary accessories and in some cases can actually lead to damage to your RV.
This said, there are also instances in which a slide support might be helpful or even recommended.
The most common type of slide jack system consists of a base with a vertical pole. At the top of the pole is a plate which can be raised to touch the bottom the slide out. When locked in place the bottom of the slideout rests on top of the slide jack, giving the slide additional support.
Solving the slideout stress problem
The problem of stress put on your RV by an extended slideout was actually solved long before you purchase your rig. Slide outs have been around for a long time. The engineers and designers at the RV companies solved the stress issues introduced by slide outs long ago. In the vast majority of cases, you can feel perfectly safe having your slides extended for as long as you need without worrying about them failing due to a lack of extra support. Its built to handle the stress of being extended.
The sealing systems which keep your slides water tight as well as the extension/retraction mechanisms in your slides are actually designed with the unsupported weight applied. Adding an extra support to take that weight off can actually damage the motion mechanism and lead to leaky seals. Both can be exceptionally expensive issues to repair. So its not just a question of how much a slide support stabilizer can help, but also a question of if it might do actual harm.
Solving the RV stability problem
While its not needed for the support, adding a slide stabilizer under your extended slides CAN help reduce the amount of rockin’ and rollin’ your RV does while people move around inside. More points of contact generally means more stability, and this is especially true on the outer extremes of the RV’s footprint.
Unfortunately, using slide supports does not address the real cause of the stability issues we all face in our parked RVs. RV’s are designed to move down a road at high speed without destroying everything inside (or itself for that matter). To do that, it is designed to have a flexible link to the ground. Tires, suspension, etc, all have give in them, even when the RV is parked. Most RV’s have scissor style support jacks which help, but they too have a lot of pivot and flex in them.
Unfortunately, if you don’t address the real cause of the stability issue then the RV will still move, but the slideout stands won’t. That puts all the stress of the movement right on the union between the RV and the slide out, exactly where it can do the most damage.
Stability issues are better solved by adding solid supports between the RV frame and the ground. By supporting the frame, the RV will be more stable while allowing the slides to remain unsupported as they were intended. The frame is the backbone of the RV and it is designed to support it. There are a number of great options to add frame support to your RV which will do an outstanding job stabilizing your RV even with unsupported slides extended.
When does using a slide support make sense?
There are a couple instances where using a slide support makes sense. The first would be if your RV is set-up permanently and you never bring the slides in. In a permanent setup like this, you have the luxury of time to fine tune how your RV is set-up. If you include frame stabilization, allow your rig to properly settle into it’s home and then add proper slide support then you can maximize the benefits of slide supports while minimizing the down sides.
The other valid use for slide supports would in the case of very old RVs or RVs which have been damaged in some way that the slides no longer support themselves properly. Correcting the problems causing the support issues would be ideal, but that’s not always practical. In those cases, slide supports can help you continue to get the most out of your RV with a minimal investment.
Conclusion – Do most RV slide outs need structural supports?
As a general rule, RV slideouts do not need additional structural supports and adding them may actually damage your rig. Slide supports can reduce some trailer movement when you are in camp, but there are better and safer methods to achieve a rock solid rig when parked. Unless there is a specific reason your slides can’t support themselves, leave the slide jacks on the shelf and save that room (and extra weight) in your RV for something you really need.
Tom Blaha bought his first RV in 2011, a 20-year-old Dutchman that he fixed up and renovated to make it road-worthy. He currently owns a 36-foot SportTrek 327VIK that he has made significant modifications to. He spent 2 years full-time RVing with his family of 6 – covering 35,000 miles and visiting 22 national parks and 43 states between 2017 and 2019. Today Tom’s family continues to enjoy RVing from their home base in the southeast US, where he also runs a small farm/homestead and a plastics machining company.