Terence is an orange crawler tractor who works near Thomas' branch line.
Thomas insulted Terence for having caterpillar tracks, but regretted it after Terence pulled him from a snowdrift.
In 1992, he helped Trevor with the planting of new trees in the forest after a storm and assured Henry that the forest would look better than ever before. He also got trapped near a level crossing when Mavis got stuck and blocked the road. When Bertie got stuck in the mud at the Vicar of Wellsworth's party, Terence used strong ropes to pull him out. Later, when villagers were stranded by snow, Terence helped them by ploughing the snow away.
In 2003 he helped clear away a tree that had fallen on the line, and pulled Elizabeth out of the snow.
Terence was helping build a barn on the day Victoria was sent back to Thomas' Branch Line. After swerving for a boulder by the Hackenbeck tunnel his trailer fell down the cutting and balanced dangerously on a tree.
In 2008, when Thomas went missing, Terence helped with the search for him, and once Thomas was found, Terence informed Harvey of the news.
In the winter of 2017, Terence took a shortcut over a frozen lake while collecting Christmas trees for the holiday market, but in the process the ice began to break. While Thomas did rescue Terence, the Christmas tree was lost.
- In the Spanish version of Keekre24's series, Terence is called Terencio.
- In the French version of Keekre24's series, Terence is called Thierry.
- Season 1: Stepney's Problem (does not speak), Thumper Saves the Day (cameo), A Scottish Tale, Toby and the New Engine (cameo), The Trouble With Spencer (cameo), Lorry Takes A Tumble (cameo), Gordon Plays a Trick (cameo)
- Season 2: A Special Visitor (cameo), A Flying Surprise (cameo), The Flying Scotsman Returns (cameo), Disaster on Sodor (cameo)
- Season 3: George the Steamroller (cameo), Cranky's Delivery (cameo), Rusty Rocks the Railway (cameo), Diesel's Dilemma (cameo)
- Season 14: Millie's Castle Hassle (cameo), Freddie at the Ready (cameo), Hiro and the Heat Wave (cameo), Furious George (cameo), S.C.Ruffey's Sweet Tooth (cameo)