From Yahoo News:
The 2.5 ton truck was flipped over onto its right side and spun 360 degrees as debris flew wildly across the highway.
The violent wind eventually flipped the truck back upright. Amazingly, the driver, who storm chaser Marcus Reynolds estimated to be about a 16 to 17 year old boy, kept driving down the road.
The driver suffered only a cut on his arm, according to Reynolds, who said he let the boy use his phone to call his parents.
The tornado was classified as an EF-2, the fourth-strongest level of tornado, according to Reynolds.