The clock is ticking for the world premiere of the new 2015 Chevrolet Colorado and its GMC twin, the 2015 Canyon, as both midsize pickup trucks will be formally unveiled this fall, before going on sale next year.

Along with a new spy video of the Chevrolet Colorado, courtesy of KGP Photography, we came to learn via an Autonews report that both GM trucks will be offered with a diesel engine option about a year after their fall 2014 market launch.

Three different sources familiar with GM’s plans told the news agency that the Colorado and Canyon will get a version of the Detroit carmaker’s 2.5-liter or 2.8-liter, four-cylinder Duramax turbodiesels, both of which are offered on the Chevrolet truck and its SUV sibling in overseas markets, in addition to the regular petrol lineup.

VIDEO