Almost every RV owner will at one point or another need a stabilizing product. What you need will vary based on the way you use your camper. Most campers will come with some sort of stabilizing jack or stabilizing component built in.
The first type of stabilizing jack is your standard manual crank jack. These jacks come in two styles. One is called a scissors jack and the other is called a telescoping jack. Both of these options are fairly light duty and are NOT (I repeat - NOT) for leveling your camper. After your camper is already leveled, these jacks will take out some of the "wobble" you experience when using your camper. These jacks, while functional, will not remove all of the sway and wobble from your camper once it is set up. The inherent problem is that the weakest point of these jacks is parallel to the direction that the tires move.
The second common type of stabilizing product on the market is power telescoping stabilizing jacks. Again, these jacks are stabilizing jacks, and NOT intended for leveling your camper. While giving slightly better functionality than the manual jack, these still have the same inherent problem as the first type, the manual stabilizing jack (see above).
This brings me to my first recommendation for stabilizing products. The BAL X-Chock is designed to remove movement from your axles by locking the tires together, significantly increasing the overall stability of your unit. Other brands have products that are intended to solve the same products. I like the BAL X-Chock because it is made of steel instead of plastic, and is much easier to handle and install than the traditional wheel chocks. As an added bonus, they are made in the USA.
5th wheel users may want to add a kingpin tripod to increase overall stability in the camper, and to add stability in the nose of the 5th wheel. The added stability will make your camper feel more solid and firm when walking inside, or during windy nights. BAL has two tripods - a light duty and a heavy duty. The heavy duty one is overall more reliable and has better functionality.
The third product that I would recommend, if the above add-ons still don't give you the desired stability, is JT's Strong Arm Jack Stabilizers. This product is a lockable arm that attaches your stabilizing jacks to your frame and removes the weak points from your stabilizing jacks, giving them a much more rigid platform. I prefer the JT's brand over the competitors for this product because theirs is an overall better product. It also comes with almost all the install components you may need for almost any application.
I consider this fourth product as overkill for any other application than for permanent sites. However, if you are set up at a permanent site, the K&S Stabilizers make your RV feel like it is sitting on a foundation, not on wheels.
This last type of jack rarely requires additional aftermarket stabilizing products. Automatic leveling systems give a very solid foundation for your camper, as they are made to level your camper from side to side and front to back. This means that they are superior in every way to the run-of-the-mill stabilizing products that other campers are built with. Depending on what type of self-leveling system you have, the only recommendations that I would have for these systems are X-chocks and Kingpin Stabilizers. Some automatic leveling systems are electric instead of hydraulic, which makes them slightly weaker. And if your automatic leveling system is a 4 point instead of a 6 point, you may need the added stability as well.
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