North American auto makers built 1,226,654 light vehicles in September, up 5.2% from year-ago, including 572,290 cars and 654,364 light trucks.

The Detroit Three produced 673,870 LVs for the month, up 3.5% from like-2011.

General Motors’ output dipped 2.9% in September and Ford slipped 1.5% from year-ago. However, Chrysler builds jumped 22.9% as it pushed to keep up with increased demand, reflected in its 21.7% gain in the U.S. sales for the first nine months.

Nissan shifted production of the Xterra SUV and Frontier pickup from its Smyrna, TN, plant to its Canton, MS, facility. Output of the LEAF electric car began at Smyrna last month.

The two plants were shut down temporarily in September to prepare for the changeovers, with Smyrna closed one week and Canton shuttered for two weeks.  The downtime was a significant factor in the auto maker’s output in the month, dropping 13.6% compared with like-2011.

U.S. LV production rose 2.2% in September, compared with year-ago, to 771,939 units and was up 22.4% to 7,584,249 in the first nine months.

Canada built 207,445 units in the month, up 11.1%. Output through September jumped 18.6% to 1,855,616. Mexico produced 247,270 cars and light trucks, compared with prior-year, up 10.5%. Output for the first nine months climbed 13.0% to 2,141,644.

North America’s 9-month production grew 20.0% to 11,581,509 units.