The left/right buttons indeed move all 3 jacks on their respective sides. One jack will move, then another and another until the first jack foot touches the ground, then another will continue travel until it touches the ground and then the last until it touches the ground. Then all 3 jacks work at a comparable rate to lift that full side up. My observation/experience. And I have used LevelUp to change a tire. More than once.
To add to JB's comment.
"If" your trailer is off the truck, e.g. disconnected and LevelUp used, the system will control all three jacks on each side as needed using the left or right buttons.
If you leave your truck and trailer connected you can still use the left and right buttons, but only the rear jacks will operate. The landing gear will remain retracted.
As you raise the trailer to clear the ground you can run into two scenarios.
One is 'out of stroke' the other is an angle issue (don't remember the exact term used).
The excessive angle issue is easily rectified by using the opposite side jacks to raise the trailer towards level. Alternate as needed to get the tires off the ground.
The 'out of stoke' message is just what it is, you ran out of stroke for the ram. Raise the jacks and add some wood blocks under the pads.
If you did the above procedure while disconnected and previously had leveled the trailer, when done just retract the rear jacks and hit the auto level button again. Just make sure anything under and close to the trailer is clear.
On the road - be prepared to have your wood blocks ready, especially if you are on the shoulder with a right side tire change.
Due to the crown on the roadway and the way most shoulders drop off, the odds are very good you will ruin out of stroke and you will have to alternate left and right to get the trailer up high enough.
The tires are heavy, the use of a 'tire spoon' is helpful.
Electric impacts are very helpful and don't forget your torque wrench.
I have done a tire change 3 times on the side of the road. Once you get your tools ready this is a 10-15 minute job, with the majority of time spent getting the spare down and back up.
Unless of course you have a nice State Trooper stand by and observe and hold the parts for you while you put everything away
In the one picture here he is holding the hub cap for me and this is after the new tire is installed ......
https://heartlandowners.org/showthr...114-s-blow-out?p=416845&viewfull=1#post416845
- - - Updated - - -
And one more thing to add.
If you have never done this - practice it once or twice before you are on the side of the road with a blowout. You really can do a tire change in 10 minutes.