Back in 2008 when Dad an I were on our way home from Idaho we saw several OTR dump trucks in WY or NE from the company "Beelman" (large trucking co. seen everywhere) that had hoses coming out of the hubs and attached to the valve stems.
We asked the drivers and they told us they were aired up by the truck system and mainly to let them keep the tires inflated while they limped to a repair shop as they were used to having many tire punctures going in and out of dumps and scrap yards.
Had seen them locally or even since then.

BK
