General Motors Co. will add a third shift to three of its plants, restoring 2,400 jobs in its second move since August to put employees in the U.S. back to work.

GM, along with rivals Chrysler Group LLC and Ford Motor Co. (F), have been attempting to respond to new demand without relapsing into its traditional habit of producing too much product and then relying on incentives to reduce the inventory.

The nation's largest auto maker by sales said last month it would increase North American production by 20% in the fourth quarter and put 1,350 employees back to work. It was GM's first production increase since global auto sales began their sharp decline last year.

On Tuesday, the company said it will add the shifts to its Fairfax, Kan.; Ft. Wayne, Ind.; and Lansing Delta Township, Mich. plants.

The Fairfax plant will become the only builder of the Chevrolet Malibu when the Orion, Mich. plant ends production in November. In 2010, the Orion plant will being retooling to produce small cars to be sold in the U.S. market in 2011. The new shift is expected to begin in January.

In Ft. Wayne, GM said it will add production of heavy-duty pickups from the Pontiac, Mich., plant that closes this month. The Lansing Delta Township facility will add the Chevy Traverse to its production. The new shifts in Ft. Wayne and Lansing are set to begin in April.

The industry's recent optimism has been attributed to the success of the government's "Cash for Clunkers" program. Auto makers posted the best sales month of the year in August, with Ford, Toyota Motor Corp. (TM) and Honda Motor Corp. (HMC) all posting sales growth. GM reported the largest decline of 20%.