On walking through your RV, you may find yourself singing a refrain from “Rock Around the Clock.” It’s true, RVs, being built light for easy (and economical) travel, are not “rock solid” in camp. The longer they are, the more they tend to rock and shake as folks move about inside. To that end, most travel trailers and fifth wheels are equipped with stabilizer jacks.
On a fifth-wheel, the “landing gear” acts as a stabilizer up front, but additional stabilizers are typically found at the rear. Travel trailer fans, if you unhitch from your tow vehicle and rest the trailer on the jack foot, you’ll certainly know the lack of stability. Many travel trailers have at least four stabilizer jacks, some have more.
How can you safely and effectively use your stabilizer jacks? First, try and park on level ground as much as possible. That saves you from having to do a lot of wheel blocking. Prior to unhitching either a fifth-wheel or travel trailer, chock your wheels to prevent any rolling. On a couple of occasions we found that standard chocks can be woefully inadequate. Hearing the shout from occupants inside the trailer as I, as chief of setup, also watched the tongue jack foot slide a couple of feet as one of those chocks let loose was a remarkably frightening experience. Visions of the trailer rolling off downhill left me with a cold sweat. We finally gave up on triangle chocks and use stop chocks that go between the tandem tires and lock them against one another—and we use them on BOTH sides of the trailer.

Wrong way: Stacking blocks under the jack foot keeps the jack from deploying properly. Photo Credit: Russ and Tina De Maris
Stabilizer jacks are just as they are described: They’re for stability, NOT for attempting to level the rig, as you’ll find if you still have the original documentation for your stabilizers. So before you set out to deploy the stabilizers, you’ll need to ensure that you’ve already leveled your rig properly.
Assuming you have your stabilizer jack instructions, we urge you to read them closely and carefully. But it’s more likely you’ll be like us, and find the original owner lost the paperwork, so we’ll fill in some general guidelines here.
First, on the subject of jack pads. It’s not a bad idea to slip a piece of wood between the bottom of the stabilizer jack and the ground. It can protect asphalt from damage, and on mooshy ground, prevent the jack from digging into the terra-not-so-firma. HOWEVER, there is a danger of using too much blocking.

Right way: The jack is extended in a way that allows for maximum load carrying capacity. Photo Credit: Russ and Tina De Maris
Here’s a position on which we’ve had to personally repent: Scissor style stabilizer jacks have their rated strength ONLY after being extended out to a certain point. Here’s a quote from one jack manual: “This jack’s weight capacity is 5,000 lb. only between 13-3/4” and 23-1/2”; the weight capacity drastically reduces as the height drops below this level. Do not apply a load to this jack below 13-3/4” in height.”
In the past we’ve used stacks of blocks under our stabilizer jacks, in part because there was less work involved—don’t have to run the jack out so far. But with this information in hand, we now use much less in the way of blocking. Yes, scissor jacks can get wobbly if extended w-a-y out. Therefore, a higher stack of blocking might be in order if you have a long way to crank out the jack.
So crank out the scissor jack until you hit resistance. Then turn the crank another rotation or so and call it good. Don’t try to crank the trailer up, and NEVER use a stabilizer jack to raise your trailer for tire changing. If it lets go at the wrong time, serious damage to the jack (not to mention the jack’s owner) can occur.
We’ve found that it was easier to repent of our past stacks of blocks misdeeds when we knew that the work would be lighter. We now use an electric drill, equipped with a “power wobbler” that allows us to install a ¾-inch socket on the drill, which fits right onto the stabilizer jack to drive it up or down as required. Using a battery-operated drill is great, as you can set the torque on the drill and not overdo it.
We also have a few “stacker” jacks that we stash away in our storage area. These critters are portable units that use a screw type device for assisting with stabilizing. Here, place the head of the jack directly under the trailer frame, NOT under an axle. Crank the jack to the resistance point, and then add another turn or two.
Properly using your stabilizer jacks can make life a lot more comfortable in the old rig, and reduce the costs of damages incurred when ignoring stabilizer jack manufacturer recommendations.
Check out Russ and Tiña’s Internet blog on a variety of RV topics at ICanRV.com.
We spend 5 months each winter in an RV Park along the Colorado River – it gets quite windy at times and our 30ft travel trailer tended to bounce around a little. Since we don’t relocate during our stay I now jack our trailer up (with a hydraulic jack) on concrete blocks and axle jack stands resting on the trailer’s 10 inch I-Beam. Very stable now and I don’t even use the scissor stabilizer jacks.
Of course, when the included jacks don’t even reach the ground when fully extended the use of blocks under them is inevitable. It was also ironic to be linked to this from the Forest River newsletter – I replaced the rear stabilizers on our Forest River Wildcat as the originals were super-chinsy.
I have read in our user manual that the x-chocks mentioned above are not to be used until after the trailer is leveled. So jacking up the tongue with them applied to attach/detach from the tv would be going against the directions and apply stress to the trailer. Fwiw.
Agreed, I never use my X-blocks until the trailer is off the truck and leveled.
We have a FR 331/2 Rockwood with 2 slides, 1 small front and 1 large back side. We always seem to be a bit wobbly. Tried several things to no avail. Our jacks are not scissors type, I guess you would call them “x-chocks” as J says above. I agree with J and never use the jacks to “lift” the trailer. We also have use the chocks that go between the tandem tires on both sides. While I feel they are safer they do not really seem to make that much of a difference. ANY Help would be greatly be appreciated
Should I use leveling blocks under the electric jacks on my Salem hemisphere 305 lite?
Hi Darrell,
Thanks for reaching out.
While we need to know a bit more about the jack manufacturer and model, but in general terms, putting a leveling block under a stabilizer jack, depending on how high the block is, can defeat the purpose of the jack itself. Many stabilizer jacks have to be extended a given length before they provide the necessary strength to do the job. If you’re in a situation where the stabilizer jack won’t hit the ground, is one thing. But if the stabilizer jack to ground distance is close enough already, it would seem just as easy to let the jack do its job unaided.
Russ
What stop chocks do you use?
All good info.
I have been trailering for at least 30 years or more in my Airstream trailer. In the older days of rallies we always had a “safety rally at least once a year.. One of the safety items that was discussed was wooden blocks under the jacks. We always recommended that at least one jack be in contact with the ground. This was in the event of a lightening strike the “juice” from the strike would pass through to the ground with no harm. Have ue ever took hold of your trailer door and felt a little tingle.. Trailer should be grounded. This is submitted as something to think about.
Good information, now to get a ground drop on my coach,
Thanks Jim
My Timber Ridge has electric stabilizers. I find that they have been better the manual ones I have had on my last 3 trailers, not to much they are more convenient. The Timber Ridge is equipped with a remote controlled unit, that works the; jacks, slide, awning and outside lights. My wife love this and has taken those jobs away from me.
Maybe you don’t know about SaveAJack, but this product can be of great help too. Saveajack is a great product that lets you easily remove your jack when moving the trailer. Taking up less than half an inch of ground clearance. Avoiding damage on the jacks and trailers.
https://www.youtube.com/watch?v=vBhRKmNNfZU
You briefly mention that the jacks need to be midway to have the best weight carrying ability, but later in the article you Only mention that they should not be cranked down too short
.”“This jack’s weight capacity is 5,000 lb. only between 13-3/4” and 23-1/2”; the weight capacity drastically reduces as the height drops below this level. Do not apply a load to this jack below 13-3/4” in height.” In other words, about half way.
You failed to mention that the least stable condition is if the scissor jacks are expended to more than three quarters or two thirds. In that case blocks do help, significantly, to provide stability. Of course it is very important that the blocks be level and solid to the ground. I have also discovered that many jacks are installed with a type of sheet metal screw. Usually self tapping. More stability can be achieved by removing these screws and replacing them with a minimum of 1/4 inch bolts and washers.
I have found that there are many misunderstandings of how to properly stabilize a fifth wheel or travel trailer from movement when parked. The best method may actually change depending on the type of jacks on the trailer.
Let’s just use the case of a fifth wheel with the standard landing gear on the front and scissor jacks on the back. The procedure discussed in the article is good to a point. It is also important to raise the frame in the rear 1″-2″ to make the rear solid. One of the problems as discussed in the article is that when one of the scissor jacks is extended it may lift loosen the opposite side. The procedure I use is to raise one side about 1 ” and then go to the other side which will be loose on the ground and raise it the same and then about another 1/2″. I then go back to the first side and raise it to the same height so both are then raised about 1 1/2″. Next, I go to the second side again and tighten it just enough to be sure the jack base is firm on the ground. The final step is to go back to the first side and be sure it is still firm on the ground. If you do this your trailer will have the minimum amount of bounce for your whole stay. It is unlikely hat you will have to adjust again unless you are on soft soil.
The above procedure will remove the bounce movement, but very little of the side to side movement since the front landing gear legs have a lot of play in them and the scissor jacks bend back and forth relatively easy.
If you want to also remove the side to side and front to back movement the most effective methods are one of the higher rated bracing systems.
If your trailer has the stab type jacks, power or manual, it is very difficult to get most of the movement out of the trailer as they tend to have give or bend in all directions.
You can find a lot more information about how to make your trailer feel solid on our website: http://www.steadyfast.com