air suspension - how can I keep the rear at the full 'height control'

[dna]

Is there any way to keep the rear at the full height when I hit the 'height control'? Mine goes up, but at about 60kms it automatically goes back down. I like the look of it at the raised height. How can I keep the truck at this height without it going down. I do not want a permanent method, as I may want to ocassionally have it go down, but I just don't want it to go down by itself at 60+ kms.

Thanks