Diesel 10 is a large diesel who lives and works at the Dieselworks.
BR Class 42
BR Swindon Works
In Adventures on Rails, he arrived on Sodor around 1962 to help with construction of the Dieselworks and restoration of Vicarstown. He was allowed to stay, and usually spends most of his time at the Dieselworks cleaning up and keeping Den and Dart in order. He will play a role in the upcoming cliffhanger between the eighteenth and ninteenth seasons.
Diesel 10 is an evil, conniving, bullying, and psychotic monster. He absolutely despises steam engines, and would call them taunting names like "puffball" and "teapot". He is Sodor's strongest but not quite largest Diesel, his power being enforced by his slightly malfunctioning claw, Pinchy. He can use this deftly, and is even able to use it to make a sculpture. All engines, steam and diesel alike, fear and respect him.
Despite his aggressiveness, he will help on occasion since Sir Topham Hatt brought him back, but only when it suits his personal interest. He can have a caring side, but he very rarely shows it.
Adventures on Rails
- Season 12 - Project 11001.
- Season 13 - New Friends, Old Enemies and Paxton and Norman.
- Season 14 - Paxton and the Blue Mountain Quarry, and James and Paxton (mentioned).
- Season 15 - Thomas and the Missing Christmas Tree (cameo) and The Fireworks Display.
- Season 16 - Den and Dart, Dodger and the Avalanche (cameo) and Thomas and the Great Railway Show Part 1 (non-speaking role).
- Season 17 - The Three Little Engines Part 3 and The Football Special.
- Season 20 - Den and Dart Save the Day and Ceremonium.
- British vs. Americans (Day of the Diesels stock footage only)
- Percy & Old Slow Coach
- Thomas, his Friends, and the Secert Island
- The End of Sodor
- The Case of the Missing Engines
- Season 1 - Dave the Diesel
- Season 2 - Dave's Scary Tale and Diesel Day (mentioned)
- Season 3 - Pompous Popularity and Cold Chaos
- Season 4 - The Missing Tool (mentioned) and The Wrong Sort of Coal
- Season 6 - The New Diesel Fuel
The Adventures on Sodor
- Season 1 - Scruff the Scrapper (original script)
- Railway Show Engines - Vinnie's Vicious Deed (mentioned) and Ivan's Devious Deed
- Tricky Twins and Kind Ladies
- According to The Real Lives of Thomas the Tank Engine, Diesel 10's hydraulic claw, Pinchy, is an illegal modification. Among other reasons, it makes him too tall for the British loading gauge.
- In an original version of the Thomas and the Magic Railroad script, Pinchy was going to be concealed beneath Diesel 10's roof. This is kept in the book, Diesel 10 Means Trouble.