Ford Motor Co. will shut down 10 of its North American assembly plants an extra week in January to adjust production with demand in the midst of the ongoing economic slump.

The normal 2-week holiday shutdown at the plants will be extended to Jan. 12.

Ford’s Dearborn, MI, and Kansas City, MO, assembly plants will not be idled the additional week, spokeswoman Angie Kozleski says, noting planned production totals will not be affected by the lengthened holiday shutdown.

“We announced in December we would build 430,000 units in the first quarter, and that included some downtime in our plants,” she says.

Ford’s Kentucky Truck Plant will be down for a longer period of time as it is being retooled to build the Ford Expedition and Lincoln Navigator fullsize SUVs, Kozleski says, while declining to reveal when the plant will resume production.

Expedition and Navigator production is being shifted from Ford’s Michigan Truck Plant to Kentucky. Michigan Truck is being retooled to produce the Focus small car.

Workers affected by the extra week of downtime will receive unemployment and supplemental pay, which totals about 95% of their normal compensation, Kozleski says.

In another capacity action, Ford will implement a “line-speed reduction” at its AutoAlliance International Inc. plant, a joint venture with Mazda Motor Corp. in Flat Rock, MI, which builds the Mazda6 and Ford Mustang.

The move will result in the indefinite layoff of about 400 employees, Kozleski says.