Chrysler Group is scheduled to start building its first salable 2014 Ram 1500 EcoDiesel pickups this month, several months later than originally expected.

Automotive News reported that the automaker plans to begin producing about 1,000 pre-spec versions — or units not based on dealer orders — powered by the 3.0-liter diesels sourced from Fiat-owned VM Motori on Jan. 21, said a person familiar with the plans. Those pickups are to be distributed to dealers in February.

A Ram spokesman declined to comment.

Dealers are expected to begin taking customer orders for the EcoDiesel-powered pickups next month. Chrysler has said that the EcoDiesel-powered Ram 1500 would enter full production in the first quarter.

Last year, Ram officials initially said that the diesel-powered light-duty pickup would be on sale in the third quarter of 2013.

Also last year, Ram brand head Reid Bigland said that when the EcoDiesel trucks went on sale, they would account for as many as one-third of the brand’s annual light-duty pickup sales. The diesel engine, combined with the eight-speed automatic transmission, produces 240 hp and 420 pounds-feet of torque, and is expected to achieve a highway fuel economy rating of around 28 mpg.

Pricing for the EcoDiesel will cost $2,850 more than a comparably equipped Ram pickup with a 5.7-liter Hemi V-8.