I found a big similarity in Pop Art and Truck Art, mainly being that they are both inspired by 'Popular Culture'. According to wikipedia;
Pop art is one of the major art movements of the Twentieth Century. Characterized by themes and techniques drawn from popular mass culture, such as advertising and comic books, pop art is widely interpreted as either a reaction to the then-dominant ideas of abstract expressionism or an expansion upon them. Pop art, like pop music, aimed to employ images of popular as opposed to elitist culture in art, emphasizing the banal or kitschy elements of any given culture. Pop art at times targeted a broad audience, and often claimed to do so.