- 2017 (new smaller face, smaller smokebox, shorter all-wooden boiler)
- Luke's first and second prototypes depicted his wheels with white rims.
- Luke's first, second and third prototypes depicted him with six wheels, when he actually has four.
- His second prototype had a green roof, whereas his final model gained a black roof.
- His third and fourth prototypes have green wheels, whereas his final model gained black wheels.
- His final model gained correct wheels, but lack the buffer detail that his first and second prototypes had.
- Luke's model has the most prototypes known of any item, with a total of four.
- Luke was originally planned to be released in 2012, but was delayed by Fisher-Price buying the Thomas Wooden Railway range and was released in 2013.
- The picture on the back of his box depicted his fourth prototype.