Diesel (AEG)

"Sparkin!"

Diesel, as his name implies, is a black diesel engine who lives and works on the Island of Sodor.

Personality
Diesel is portrayed as one of Thomas' best friends. He is Thomas' competitive friend, always trying to one-up Thomas, and inadvertently causes trouble for everyone in his quest to be "the real Number One Engine." However, he does still retain some of his original personality, like trying to sabotage others in order to win a race. But despite this, he still has his limits when it comes to sportsmanship, especially after he witnessed his favorite racers, Farona and Frederico try and sabotage Thomas and Kana's chance at winning the Sodor Cup.

Basis
Diesel is based on a British Rail (BR) Class 08 diesel-electric shunter. In the real world, BR Class 08s were in fact the most successful shunting engines in the world with 996 of them built. Over seventy of them are preserved by heritage railways, such as the Dean Forest Railway and museums, such as the National Railway Museum. Around one-hundred BR Class 08s also remain in service on the national rail network.

Livery
Diesel is painted black with a dark purple stripe along each side and dark purple toolboxes and wheels. His valences and running board are also dark purple, while his bufferbeams are red.

During Race for the Sodor Cup, Diesel briefly wears a special livery in support of Farona and Frederico which is similar to his normal livery, however with a few notable differences. Namely, his running board and the stripe along his side are yellow, with an additional orange stripe in the middle and a yellow box under his face. After witnessing them cheat in an attempt to preserve their chances at winning, Diesel reverted back to his normal livery after Kana and Thomas crossed the gap.

Appearances
Television Series= {{Scroll box|

Thomas & Friends: All Engines Go

 * Series 1 - A Thomas Promise, Thomas Blasts Off, License to Deliver, Rules of the Game, A Quiet Delivery, Kana Goes Slow, Dragon Run, The Biggest Adventure Club, A Wide Delivery, Chasing Rainbows, Nia's Balloon Blunder , Capture the Flag, Super Screen Cleaners , The Joke is on Thomas, Thomas' Day Off, The Real Number One, No Power, No Problem!, The Tiger Train, Calliope Crack-Up, Tyrannosaurus Wrecks, The Super-Long Shortcut, A Light Delivery, The Paint Problem, A Wonderful World, Whistle Woes, Letting Off Steam, Something to Remember, Sandy Versus the Storm, An UnbeLEAFable Day, Ghost Train, A Rusty Rescue, Hide and Surprise!, Pop a Wheelie, Goodbye, Ghost-Scaring Machine, More Cowbell, Sir Topham Hatt's Hat, Nia's Surprising Surprise, A New View for Thomas, Skiff Sails Sodor and Song of Sodor
 * Series 2 - Percy Disappears, Shake, Rattle and Bruno, Ashima's Amazing Arrival, Tri-and-a-Half-a Lon, Carly's Magnificent Magnet, Carly's Screechy Squeak, Blackout!, Brand New Track, Stink Monster, Christmas Mountain, More Than a Pretty Engine, Snowplow Struttin', Thomas in Charge, Kana Recharges, The Big Skunk Funk, Off the Rails, Diesel's Dilemma, Bring it on Beresford, Sheep Shenanigans, Tunnel Troubles, A Very Percy Valentine's Day, Valentine's Hearts, The Case of the Missing Crane and Salty's Sea Shanty
 * Series 3 - TBA
 * Short Story Adventures - Diesel's Rules, Nia and the Ducks, Muddy Thomas, Diesel's Seagull, Surprise!, Lighthouse Disco, Horrible Hiccups, Hay, Now!, Red Light, Green Light and Confetti Car Kerfuffle

Specials

 * 2021 - Race for the Sodor Cup
 * 2022 - The Mystery of Lookout Mountain

Songs

 * Series 1 - All Engines Go Theme Song, I'm Gonna Chug, Knights of the Turntable, A Partner on the Rails, The Mail Delivery Song, If I Was a Super Train , Get on the Laugh Track, What Brave Engines Do , Feet, Tailbone, Ribs, and Claws, The Number One Engine , What's Awesome About This Place, A Gift to Remember, Fall Fun, My Rusty Can, Together We Can, Celebrate and Song of Sodor
 * Race for the Sodor Cup - Look It's Us
 * Series 2' - You Can't Stop Me!, A Mistake is What it Takes, Plow to Have Fun on the Job, Feel the Hush, What's Really Real , What I Can Do and What I Can't, Peep Peep, We're Counting Sheep and How to Solve a Mystery
 * The Mystery of Lookout Mountain - Warning: Biggest Adventure Ahead, A Whole New Place and Job to Do
 * Other - All Engines Go Theme Song and Train School Song

Videos
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 * Let's Race - The Egg Race, The Bell Race, The Flag Race and The Obstacle Race
 * Train School - Under the Meadow, The Magic of Patience, The Height of Courage, The Run Down, The Team-up Cleanup and The Art of Sharing
 * All Aboard! - Detective Bruno and The New Platform
 * Sodor Mystery - Thomas and the Mysterious Delivery and Mystery of the Missing Watermelons
 * -|Other Media=

Magazine Stories

 * 2022 - Shake, Rattle and Bruno! and Thomas' Day Off
 * 2023 - License to Deliver, A Quiet Delivery and Tyrannosaurus Wrecks

Books

 * 2021 - All Engines Go
 * 2022 - The Promise Problem, Thomas and the Rocket, Imagine Ink, Speedy Sticker Scenes, Meet the Engines and Thomas the Tank Engine Character Encyclopedia
 * '2023 - Thomas and Bruno, Tyrannosaurus Wrecks and The Twelve Engines of Christmas

Games
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 * 2022 - Magical Tracks and Musical Tracks

Trivia

 * In an early version of the script for A Thomas Promise used for auditions in January 2020, Diesel is renamed Joey, in order to keep the series a secret.
 * Diesel is one of only three engines from the original series to still have cab doors, the other being Whiff and Kenji.