It's finally showtime for the most important new vehicle launch from Ford in decades.
The first of the new aluminum F-Series pickups is rolling off the assembly line at Ford's historic Rouge assembly plant. Within a few weeks the new pickups will be in showrooms.
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"This is probably the biggest leap of faith with the Ford F-series ever," said Jack Nerad with Kelley Blue Book. "This is a giant leap because they have changed the vehicle very significantly in terms of construction. When you go from an all steel body to an aluminum alloy body, it is a big, big change."
Some call it a gamble.
After all, going from panels built primarily out of steel to panels built primarily out of high strength aluminum required Ford to re-tool its truck plant in Dearborn. And while greater amounts of aluminum are now used in a whole host of vehicles, this is a major shift being applied to the best-selling vehicle in the world.
Which raises the question, how will we know if Ford's new truck is a hit?
Sales
It will take time for the new F-Series to roll into showrooms. After all, Ford is just ramping up production.
Truck buyers are among the most loyal in the auto business and there should be no shortage of buyers.
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The real issue is whether Ford will be able to command the 4 percent to 5 percent premium it's traditionally enjoyed compared with the Chevy Silverado and GMC Sierra pickups.
Clean Launch
This is what investors will be watching closely.
That includes Matt Stover, who covers the auto industry at CIG Research, which makes a market in Ford securities.
"Look, every new vehicle launch has some issue. The question is whether Ford can avoid major hiccups," he said.
Stover and others on Wall Street will be watching to see if Ford's "scrappage rate"—pieces of the new trucks that are scrapped because of problems—is unusually high as the company starts stamping aluminum panels and boosting production.
"If Ford can limit the problems and get the scrappage rate close to what it has been for other new vehicles, the new F-Series will have a good shot at having a strong launch," he said.
Durability
For decades, the F-series truck has been known for its toughness.
Ford's Joe Hinrichs, who runs the automaker's operations in North America, is confident that won't change with the new F-Series.
"We made sure we didn't compromise with this truck," Hinrichs told CNBC at an F-Series test drive in Texas.
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"You drove it, you saw how it handled rugged conditions," said Hinrichs.
True, it performed well while being driven through a challenging off-road course. But it's another whole thing to have contractors beating up a truck over the course of several months.
If the new F-Series holds up well over time, then the new truck will build on Ford's reputation as build tough, reliable trucks.
The bottom line is we won't know for several months if Ford's new F-Series trucks will pay off and reward the automaker's leadership with taking the bold step to build aluminum pickups.
Questions? Comments? BehindTheWheel@cnbc.com.