Adjusting HWH Leveling Jacks

During our first few months living in Rover we realized that our auto-leveling jacks weren’t quite working as expected. Very few campsites we’ve been to (if any) are perfectly level, so the “auto level” function is supposed to extend each of the four corner jacks an appropriate amount, lifting Rover’s left, right, front, or back (or a combination) up a bit until he’s level. We often felt that our back-left corner was lower than the rest of the RV, and some testing with a bubble level confirmed it.

While we were at Lazydays in October for repairs, we had them show us how to adjust the auto-leveling calibration. We had looked in all our manuals, and online, but could not find the right process for our equipment. Now that we know how to do it and have successfully recalibrated what “level” is, we thought it would be good to explain the process here for anyone else in our situation. There are several different leveling systems in use today, and each has a different process, so this process may not apply to your leveling system.

Our 2014 Tiffin Allegro Open Road 36LA has an HWH system with the calibration control unit bolted to a wall in the storage bay that houses the hydraulic system for the jacks and slide-out rooms. Here’s what it looks like:

Location of the leveling calibration unit.

Location of the leveling calibration unit.

The bottom of the unit has four lights in a diamond pattern that represent the front, left, back, and right sides of the calibration unit (see red arrow in the photo below). A light will come on if that side of the unit is lower than the others. The lights work the exact same way as the four lights on the dashboard leveling controls. When all four lights are out, the unit is level.

The need for calibration arises because the motorhome’s jacks extend until the calibration unit is level. However, if the unit’s horizontal plane is not exactly aligned with the motorhome’s chassis, the the motorhome won’t be level. For example, if the unit is mounted in the storage bay so that it’s back half is slightly lower than its front half (maybe the wall of the storage bay isn’t perfectly vertical), it will extend the rear leveling jacks until the unit is level. However, this would make the rear of the motorhome higher than the front.

There are three screws on the bottom corners attached to three springs (see yellow arrows in the photo below). These correspond to three of the four leveling jacks under the motorhome. Tightening or loosening these springs will tilt the calibration unit, with the goal being to make the unit just as level as the motorhome. Only three screws are needed, since lowering the front-left, back-left, and back-right accomplishes the same result as raising the front-right which has no spring.

Automatic leveler calibration screws and lights.

Automatic leveler calibration screws and lights.

Since auto-leveling keeps making the back-left of Rover too low, that means that the calibration unit’s back left corner is too high compared to the motorhome. Turning the back-left screw counter-clockwise will lower that corner of the unit, so the next time auto-leveling is done, it will need to extend the back-left jack a further before it senses that it’s level. For us, this means Rover’s back-left corner will be higher, and we’ll be more level overall. Turning clockwise of course does the opposite, raising a corner of the calibration unit, resulting in the corresponding corner of the motorhome being lower.

Usually just a quarter turn of the screw will result in a noticeable difference when auto-leveling. We’ve also found that a lot of patience is needed to get it “just right”. After auto-leveling, I’d make a small adjustment to the screws but I’d then wait until our next campsite (maybe a week later) to see what kind of difference it made. If more adjustment was needed, I’d make the change and check the results at the next campsite.

Hopefully your motorhome doesn’t need adjustment, or maybe you have a higher-end leveling system that allows calibration right from the dashboard. If not, I hope these instructions will help you get level!

Michael Fischer

After a high-tech career spanning software development and systems administration to leading hundreds of engineers across cities and continents, I'm now slowing things down a bit. Traveling full-time in an RV with my awesome wife Kathie and our two big dogs Max and Opie, I'm now pursuing smaller personal software projects while seeing North America up close.

1 Comment

  1. chuck spear   •  

    Could you send that info on how to adjust your auto level on tiffin 36LA 2014 to my email. Thank you.

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