Corrected entry: The rescue mission in this movie references Toy Story 2 in several ways. One is crossing a street hidden under everyday items. Another one is going into a skyscraper to save a friend. Another is traveling through an air vent.
Corrected entry: When at the dog show, before Garfield runs out, all the dogs are being held by their leashes and collars. When they chase after Garfield for the next minute or so, they have on no collars or leashes.
Correction: When the dogs take off after Garfield they obviously slipped out of their collars to chase him.
Corrected entry: When the pets escape from the dog pound, we get a shot from the outside as they run out the door onto the stairs. But the door opens INWARD.
Correction: Some doors open inwards, all based on how the hinges are placed.
Corrected entry: Bill Murray is the voice of Garfield. He also played Pete Venkman in Ghostbusters. The same voice actor who played Garfield in the cartoon series also did the voice of Pete Venkman in the cartoon, "The Real Ghostbusters."
Correction: A clarification on the voice of Pete Venkman in The Real Ghostbusters ... Lorenzo Music (the original voice of Garfield) did the voice in 1986-1987, after that Dave Coulier did the voice of Peter Venkman from 1987-1991. Just so no one mistakes Dave Coulier as the voice of Garfield.
Corrected entry: There is no license plate on the front of Liz's Nissan Pickup.
Correction: Not all states require a licence plate to be mounted on the front of a vehicle.
Corrected entry: How did the old woman, who picked up the sausage dog from outside, know the name of the dog? There was no collar with a tag on its neck.
Correction: She didn't, her posters said 'dog found'. When Happy claims Odie is his pet, he tells her that he responds to Odie which he learned at the dog show.
Correction: I don't think this is trivia, as it is too obvious.