Fergus is a Traction Engine whose main function is to shunt trucks at the Cement Works. It's dusty work and has left him with a slight but persistent cough, which punctuates his speech. Fergus is a reliable down-to-earth character, who believes in playing by the rules (he knows the Rule Book off by heart). Unsurprisingly, he's resistant to change and can be irritated when other engines "muck about." Physically, Fergus is blue with red wheels and a tall funnel.

He has a flywheel which can be used to power tools, such as a saw, drill or pump.