Class 40 (T&F)

"Look at me Duck and Stepney. Now I’ll show you something."

- Class 40 bragging to Duck and Stepney Class 40, also known as The Diesel, D261 or simply Diesel, is a big green diesel engine who once visited the North Western Railway on loan from British Railways.

Biography
Class 40 was sent to Sodor to assist the engines with goods and express work towards the end of Stepney's visit, but he only insulted the other engines by saying they were out-of-date, should be scrapped and bragged about how much better he supposedly was. Unfortunately for him, an inspector's bowler hat jammed his air intake, causing him to break down and to become as sick as boiler sludge after attempting to show off to Duck and Stepney. He sulked in the shed while Duck and Stepney took the Express for him to Crovan's Gate.

While everyone was fare-welling Stepney, a disgraced Class 40 crept away, leaving behind "a rather nasty smell and a battered bowler hat".

Personality
Class 40 is snobbish, smug and rude with his snide remarks, believing that diesel engines are superior and should take over from steam engines while also showing off to engines such as Duck and Stepney. In the end however, he would also show his cowardly side as shown when he slipped away after his embarrassing incident when no was looking. Despite this, in the magazine stories, there are some occasions in which the Diesel is polite and helps out the steam engines, even if he was reluctant.

Basis
Class 40 is based on a British Rail (BR) Class 40 1Co-Co1. Old Stuck-Up and D782 from The Railway Series are also members of this class. 200 members of this class was built from 1958 to 1962, and the last was withdrawn in 1985. They were given the nickname "Whistlers" because of the strange whistling noise their engines would make. Seven Class 40s are preserved with the first built, D200, at the National Railway Museum.

Class 40's number belonged to a real Class 40. The real D261 entered service on the 26th of February 1960, initially built with the 'disc' headcode marker. In 1965, it along with Nos. D260-D266 would then be converted with the 'central' headcode marker and were based in the Scottish Region. Sometime between 1965 and 1970 it was repainted into BR rail blue. In 1973 it was renumbered to 40 061 until the engine was withdrawn from service in 1983 and scrapped at Crewe in March the following year.

Livery
Class 40 is painted in the BR Deep Bronze green livery. He has a thin, lighter green stripe running along his top, full yellow warning panels on his front and back end with his rooftop painted black and shining silver buffers as opposed to the regular grey buffers. His number is painted on his cab sides in yellow similar to the Railway Series illustration. His face is grey like the other engines.

Appearances
Television Series= {{Scroll box|

Thomas & Friends

 * Series 4 - Rusty to the Rescue and Bowled Out

Music Videos
}} Other Media= {{Scroll box|
 * Series 4 - Thomas' Anthem Grand Finale
 * Series 5 - Come for the Ride
 * Series 7 - The Whistle Song

Books

 * 2004 - Oliver
 * 2008 - Thomas' Sticker Express
 * 2011 - Oliver the Great Western Engine
 * 2017 - Oliver

Magazine Stories
The Diesel also appeared in the magazine stories, Blowing About! and Diesel Display.
 * 1998 - Rusty and the Cheeky Boys
 * 2001 - Diesel Day! and Dusty Diesel
 * 2002 - Just Right and Dusty Diesel!
 * 2003 - The Big Hero
 * 2006 - Heavy Load, Sounds Better and Bridge Bother
 * 2007 - Platform Picture
 * 2008 - Superhero! and Left Alone
 * 2010 - Proud Puffers
 * 2011 - Team Effort
 * 2012 - Tender Trouble, Team Effort!, Story Time with Thomas and The Railway Show

Video Games

 * 2008 - Begins Educational Learning

Video Releases
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 * 1995 - The Thomas the Tank Engine Man

Official Description
1995-2000= From Official Website:

From Official Website:
 * -|2000-2005=

From Official Website:
 * -|2010-2020=

Trivia

 * Class 40 is called "Diesel 261" in Japan.
 * According to some VHS descriptions for the fourth series episode Bowled Out, Class 40 was brought to Sodor to take over Daisy's work while she was ill.
 * Class 40's nameboard sequence has only appeared in Cranky Bugs and Other Thomas Stories and in the airings of Bowled Out in Japan.
 * In the magazine story Platform Picture, he is incorrectly referred to as "Derek the Diesel".
 * His Hornby model depicts him as a Class 37 diesel which still has an inaccurate number for a locomotive of this type.
 * In the Days Out with Thomas events, Class 40 wore Toad's face.
 * Class 40's model is currently on display at Drayton Manor Theme Park with his speechless face.
 * Series 10 production notes incorrectly call him "Diesel 140". Series 12 production notes call him "Diesel 40".
 * Class 40's Take 'n' Play model incorrectly depicts him with a Bo-Bo wheel arrangement. This was likely due to the fact that the manufacturers could not depict him with his correct 1Co-Co1 arrangement. It also appears his side detailing was incorrectly based on that of a Class 37 diesel much like the Hornby Model.
 * His horn sound was reused for Mavis in the fourth series episode, Thomas and the Special Letter.
 * Class 40 had a total of six facial expressions, one of which (a cross face) was never shown on-screen. However, his happy face is only on his face references from the fourth series, but not on his face references from the sixth and twelfth series. It is possible that his happy face was either lost or destroyed during or after filming of Thomas and the Magic Railroad.
 * His engine sound is shared with BoCo from the fourth-fifth series, as well as Rusty, but only in the fourth series episode, "Rusty to the Rescue".
 * Class 40 and Derek share the same livery.
 * Interestingly, a few of his faces were based/inspired from the Illustration from Stepney the "Bluebell" Engine, most notable being his speechless face from the third illustration and his smiling face from his prideful face in the first illustration to some extent.
 * Although Class 40 did not appear in the fifth series, his theme from Bowled Out when he breaks down is heard in Cranky Bugs when Cranky is rescuing the engines from what remains of the shed. His theme can also be heard in other episodes from the fourth series. And it was last heard in the sixth series episode, Dunkin Duncan when Duncan arranges his four trucks.