Chrysler Group LLC will add 1,250 workers at three U.S. plants to boost output of pickups and engines, Bloomberg reported.

Chrysler plans to invest $238 million in the factories, including the Ram 1500 assembly plant in Warren, Michigan, according to a statement. The Warren factory will add a third crew of workers and 1,000 new jobs, Bloomberg said.

Chrysler will invest $198 million and as many as 250 jobs at its Mack I Engine plant in Detroit to boost production of the Pentastar 3.6-liter V-6 engine. Another $40 million will be invested in the Trenton North engine factory in Trenton, Michigan.

The Mack I plant currently builds V-8 engines, but that line will be phased out and the plan will shift to producing only the Pentastar engine by early 2014, Bloomberg said.