Hey Lil Giant's, watch the video again,(2:00 minutes) when they show the close up of the tractor tandem's, there are air hose's sticking out from the drive hub's to an arm. They can adjust the tire pressure on the fly!
http://auto.howstuffworks.com/self-inflating-tire2.htm Read the CTIS blurb. No offense taken, just seeing the small stuff! Later, doodlebug