When you arrive at the site, perform a level check by placing a bulls-eye level in the open doorway.  If you prefer, external indicators are available at many camping supply outlets and can be easily installed on the towable for use in place of a bulls-eye level. 

Wood planks, plastic blocks and inflatable levelers are common leveling apparatus.  For side-to-side leveling, place the leveling device on the ground in front of the low side wheel, and using the tow vehicle, slowly pull the trailer into place on top of the leveling device.  Set the parking brake on your tow vehicle and inspect the leveling indicator for accuracy.  Your level indicator should be within one-half bubble of center.    If you are new to this procedure it may be necessary to add or remove blocks to obtain a desired level, however, with time and practice you will soon learn to quickly gauge the necessary height.

Prior to unhitching the towable, disconnect the tow plug and breakaway cable.  Position chocks on both sides of the wheels as a safety precaution to prevent the trailer from rolling even when parked on a level surface.  Next, go to the front of the vehicle.  If the trailer is sitting high in the front, it may be necessary to extend the landing gear or tongue jack a considerable distance before unhitching the tow vehicle.  If the trailer is sitting low in the front, place blocks under the landing gear or jack to avoid over-extension.

Once you unhitch the tow vehicle and level the towable front to rear, it is then time to lower the stabilizer jacks.  Use blocks when there is excess distance between the jacks and the ground surface.  Stabilizer jacks are designed to maintain the trailer in position.  Do not use stabilizer jacks to raise the trailer or to support trailer weight and risk damage to the jacks and trailer frame.

If your trailer is equipped with an auto leveling power tongue jack, battery power is required to operate the system.  If the jacks fail to operate and the battery is charged, check for a blown fuse in the breaker panel.  You will hear a change in motor sound when the jacks are fully extended or retracted.  At that time, release the switch to prevent damage to the system from overheating or clutch slippage.

After hitching the trailer to the tow vehicle, confirm the trailer is fully latched into position before raising the jacks.  When it’s time to raise the jacks, be sure the jacks are fully retracted before towing the trailer.  Remove the wheel chocks, and remember to take the leveling blocks with you before you drive away. 

The slide out rooms can be extended after leveling the towable if the ground is reasonably level.  However, when the site is angled more than 3 to 5 degrees, it is recommended to extend the slide rooms prior to leveling.  When you do not intend to level the towable at all, for example, while loading or unloading, the slide room can be extended for a brief period of time.