Thomas the Tank Engine Wikia

Class 40 is a big green diesel engine who once visited the North Western Railway on loan from British Railways. This diesel is considered to be a little snooty by the other engines because of his "know-it-all" attitude, which "steams up" the steam engines. Despite his immense power, he soon left in disgrace after an incident with an inspector's bowler hat.

Did you know? He is also often referred to by his number D4711 (D261 in Thomas & Friends) or simply as The Diesel.