This happened south of College Station, TX yesterday evening. I don't remember ever hearing of a lightening strike on a vehicle traveling down the highway. I guess it can happen!
http://www.kbtx.com/content/news/Tractor-trailer-catches-fire-after-lightning-strike-477229313.html
http://www.kbtx.com/content/news/Tractor-trailer-catches-fire-after-lightning-strike-477229313.html