Do I need to use a 10-22mm or 15-85mm EF~S lens?

I took 'side view' pics of Fire Trucks and Firemen during a Pre-Parade Inspection. I used the standard 18-55mm EF~S from about 15 feet away. I can't move back any further. I'm losing about 6-8 feet of the truck. Trying again this 4th of July.... Should I use a 10-22mm EF~S or 14-85mm EF~S? I want the entire truck in the pic, but I don't want curved edges (distortion) on the pictures.