Road Games, by Richard Franklin

A suspenseful thriller about a truck driver's efforts to stop a demented murderer. Pat Quid has been hired to deliver pork to Perth, Australia. Keeping him company on the road is his pet dog, who Pat claims is a dingo. After hearing about a killing spree, whose culprit remains unknown, Pat starts to believe the fiend is actually the mysterious driver of a green van he passed along the way. When the police don't believe the story, Pat decides to nab the villain on his own. After the maniac kidnaps Pamela, the pretty hitchhiker Pat picked up, the truck driver becomes even more determined to stop the madman.