Road Train is an Australian horror film, known as Road Kill in the U.S., directed by Dean Francis and written by Clive Hopkins. It stars Xavier Samuel, Bobby Morley, Georgina Haig and Sophie Lowe.
Nina discovers the trucks fuel tanks are empty, but finds a large pipe underneath the trailer, filled with a mysterious red goo. Craig, tormented by visions of the hellhound Cerberus, finds a key to the trailers. He opens the rearmost trailer and heads in, and the door closes itself behind him. Marcus and Liz have a disagreement over her having slept with Craig. Liz storms off, while Marcus stays on the road. Marcus has a runin with the trucks driver who shoots himself. Liz finds the shack rundown and abandoned. Inside, she finds unlabeled cans containing the red goo. Thirsty, she drinks some, but quickly runs back after finding bloody remains.Liz and Nina try to start the truck, but Marcus, now wearing the truck drivers clothes and carrying his gun, trying to destroy it. The women overpower him, tie him up, and resume working on the truck. Craig emerges from the trailer and kills Marcus. The truck starts up again, and Nina tries to back it up. Liz stands at the rear to signal Nina, but eventually leaves to drink more red goo. Nina, unable to see Liz, exits the cab and sees Craig, who tries to lure her into the rear trailer. Hearing Liz crying for help from inside the trailer, she pushes Craig in and locks the door. Eventually, Nina successfully turns the truck around and returns to the main road. She stops the truck and examines the front trailer. To her horror, she discovers it is a slaughter house. Human bodies, including Marcuss, are ground into the red goo that fuels the truck. Shocked, she returns to the cab and keeps driving. ........
Source: Wikipedia