The DL class were the first Diesel powered locomotives in the state (not including railmotors). DL1 is the oldest, built in 1939 at the Ipswich Workshops.

The DLs were used exclusively in the Atherton Tablelands, due to the lightly laid rails. They were later used for shunting elsewhere in the state.

Its quite interesting to note that all four members of the class still exist to this day, with two in operating condition. DL1 is preserved with QR Heritage, DL2 is on display in its namesake town of Forsayth, DL3 is based at the ARHS-Qld Rosewood Railway where it is regularly used for shunting and last but not least DL4, which is still in service with QR on the Normanton – Croydon line.