Other mistake: The end credits show Annie, Clarabel, Bertie and Harold under the voice cast for "the trains", but Annie and Clarabel are rolling stock, Bertie is a road vehicle, and Harold is an aircraft, respectively.
Other mistake: During the chase scene as the engines go through the tunnel, there is a figurine sitting on the back of Diesel 10. This happens to be the film's original antagonist, P.T. Boomer who was cut from the movie. However, the crew forgot to remove the Boomer figurine from Diesel 10.