Roy is a tugboat mentioned by Mater.
Cars: The Video Game Edit
In the second deleted scene, Mater was talking with Lightning, the topic over the first and second scene had changed from Bessie to their dreams, Mater said he had a weird dream that he was a tugboat named Roy. He described it as follows: "It was a horrible dream! I can't even swim! I don't even go to a Car Wash!".