DETROIT (Bloomberg) -- Ford Motor Co. has begun an eight-week closure of its F-150 pickup plant near Detroit to overhaul it for a new, aluminum-bodied version of the top-selling vehicle line in the U.S.

“This is historic for the industry, not just for Ford,” Joe Hinrichs, Ford’s president of the Americas, told reporters today at the company’s product development center in Dearborn. “To take the No. 1 selling vehicle for 32 years -- it will be 33 soon -- and convert it like this, at this volume, to aluminum, is historic and unprecedented.”

Michigan workers assembled their last 2014 F-150 early on Friday and crews began tearing up the plant to make way for the new equipment necessary to manufacture parts out of aluminum, Hinrichs said. The conversion began one day ahead of schedule, he said, and this weekend, 1,100 trucks will stream into the plant to deliver the new tools. By mid-October, the factory will be building the “production version” of the 2015 model, he said.

“This is a massive undertaking, one of the bigger logistical challenges we’ve ever seen,” Hinrichs said. “It’s been orchestrated literally by the minute, by the truckload.”

The redesigned F-150 is the most critical new-model introduction for Ford in a year in which it is debuting 23 new products worldwide, including 16 in North America. Ford’s U.S. sales are off 0.4 percent this year and the automaker has said 2014 profit will slip as it retools factories and spends to introduce new models. Ford had net income of $2.3 billion in the first half of the year, compared with $2.84 billion in 2013’s first half.

While Ford overhauls its Dearborn truck plant, it will continue to produce the 2014 model F-150 at a factory near Kansas City, Mo. That factory will close next year to be converted to the new aluminum-bodied pickup, Hinrichs said. Ford has said it is shutting its two U.S. F-series plants for a combined 13 weeks this year to prepare for the new model.

Including beefier versions, such as the F-250, the F-series has been the best-selling truck line in the U.S. for 37 years and the tops in the industry for any vehicle type for 32 years.

The F-150 arriving in showroom at year’s end sheds more than 700 pounds (318 kilograms) to improve fuel economy, mostly by using aluminum instead of steel in its body. In 2013, Ford’s U.S. F-Series sales rose 18 percent to 763,402. That helped drive Ford’s North American pretax profits to a record $8.78 billion last year. So far this year, F-series sales in the U.S. are up 0.3 percent to 429,065, according to the Automotive News data center.

“We’re very much on plan,” Hinrichs said. “F-150 is roughly one out of five vehicles we sell in North America. So it’s a big deal and no one’s ever done this.”