Ligety overturned a 1.22-second deficit from the slalom to beat Pinturault by 0.22. Natko Zrncic-Dim of Croatia was third, trailing 1.08 behind Ligety's combined two-run time of 2 minutes, 44.74 seconds.
Pinturault suggested he and Ligety are the main medal contenders in the Sochi super-combined scheduled for Feb. 14.
"Yes, of course. The big challengers for me is going to be Ted Ligety and Ivica Kostelic, for sure," said the 22-year-old Frenchman.
Ligety, Pinturault and Marcel Hirscher are the established big three in a high-class giant slalom line-up, and the American's latest downhill display suggested his world title in super-combined was no fluke.
"I had a way of figuring out how to win the big events, like Olympics and world championships, in combined but never put together the runs I needed to win a World Cup," said Ligety, who won at the 2006 Turin Winter Game when the combined included two slalom legs.
On Friday, the coaches' strategy for Ligety's downhill was fine-tuned by Miller's radio briefing, minutes after he skied down to an eventual ninth-place finish on a soft course worsening fast in mid-afternoon sunshine.
"Bode confirmed a couple of things where you could trim the race line and avoid a couple of holes," Rearick said. "We changed the report a few times on many sections and Ted executed every one of them beautifully and aggressively."
"That was impressive," the U.S. head coach said.
Miller, the reigning super-combined Olympic champion, finished 2.15 seconds behind Ligety after being seventh fastest in tricky slalom conditions in the morning.
Aksel Lund Svindal of Norway finished fifth and took the overall World Cup lead from Austrian rival Hirscher, who skips speed events. Svindal earned 45 World Cup points to lead Hirscher by 22
Svindal posted the fastest downhill time Friday, suggesting he could challenge for victory in Saturday's classic downhill for the first time in his storied career.
Ligety also extended his advantage over Pinturault in the race for third place overall. Ligety trails Svindal by 264 points.
The expected challenge by Kostelic, the Olympic silver medalist in both 2006 and 2010, ended early when he straddled a slalom gate. The veteran Croatian is a six-time winner in slalom and super-combined in Wengen.
Organizers ran the slalom first on Friday to give time for cloud cover to clear and also to prepare the shortened, 3.1-kilometer (1.9-mile) downhill course after heavy overnight snowfall.
Today, the 84th Lauberhorn race will follow the full 4.42 kilometers (2.75 miles) course, twisting beneath the Eiger mountain.
Miller will seek his third victory, after wins in 2007 and '08. He was also runner-up the following year.
Ligety will take a day off to rest before Sunday duty in the slalom.