The truck uses the entire "flammable" tank as a gas tank.
That's why it can keep going and never refuel Mann's wife hired the truck to kill Mann
Hence why she says he shouldn't have had to call. This is all in Mann's head
As he aimlessly drives the countryside. The film is a prequel to Maximum Overdrive
The aliens controlling the trucks were still working things out - they tried taking over the human owner of the truck. Because it failed in the end, they decided to just keep it to the vehicles themselves.- The mere suggestion that this classic could have any relationship whatsoever to Stephen King's worst film is itself an atrocity.
The truck driver is Robert Dupea from Five Easy Pieces
Robert bought the truck from the end of the movie and started to work again for his old oil company.