Troublesome Trucks (called Cars in the US narration) are always nicknamed because they can be very troublesome and love to play tricks on the engines, except Edward, Stepney, Geoffrey, Hiro, and Salty. The trucks have been the cause of most of the railway's accidents. However, since Douglas smashed the Spiteful Brakevan and Oliver pulled S. C. Ruffey, their leader, apart, they have been frightened of some engines.
There have, however, been some cases where the trucks and engines are on the same side, such as when Diesel was given a third chance on Sodor, but the trucks tricked him into misbehaving and getting sent away again.
Every wise engine knows trucks cannot be trusted. Trucks could be considered the rebels and the troublemakers of all rolling stock on the railway, as most of them love to cause mischief and trouble and show no remorse for whatever they do. If an engine is having a bad day, makes a mistake, or is easily played upon, then the trucks begin their wild antics of singing, name calling, holding back, shoving, bumping, giggling and so on. They will play tricks on an engine based on how they treat them. Most accidents caused by the trucks are a form of revenge due to mistreatment, and they are not known for considering the consequences of their actions; they will carry out their plans even if they result in derailing, damaging or destroying themselves.
- Season 1 - Harvey's Goods Train and Fishy Troubles
- Season 2 - Molly's Coal Delivery
- Season 3 - Hector the Ballast Hopper
- Season 4 - It's Not Easy Being Green
- Season 5 - Samson and Logan
- Season 6 - James and the Royal Train
- Season 7 - Ryan and the Trucks
- Season 8 - Bradford Returns