DeChambeau shot a 6-under 66 to match Uihlein at 16-under 197 at TPC Summerlin.
"Definitely nice to be able to ball strike it as well as I have the past three days," DeChambeau said. "Nice to be able to take two weeks -- or three, four weeks off. I don't know how many weeks I was off. It's nice to not know essentially coming into an event and still be able to perform. That's something I'll take with me moving forward."
The leader after each of the first two rounds, Uihlein had a 68. He's winless on the PGA Tour.
"I wouldn't really say I was overly frustrated," Uihlein said. "I didn't feel like I hit it probably close enough as I probably could have to feel like, 'Hey, these are really makeable.' I didn't feel like I missed any putts I should have made."
DeChambeau has four PGA Tour victories, winning three times last season.
"Still not seeing the line as well as I would like to," DeChambeau said. "It's all visual. If I start seeing it really well, watch out. But if I don't see it well it's a struggle. I'm going to go work on that and try and make that better for tomorrow."
Lucas Glover was a stroke back after a 61 that he capped with his second eagle of the day. He eagled the par-5 13th on his opening nine, and closed with another eagle on the par-5 ninth.
"Made some putts," Glover said. "I started out with a bogey on 10, actually. Hit a good putt, just misread a 4-foot slider. Made everything else, that's for sure. Couple eagles on the par-5s. Holed it like a bucket. One of those days."
"I like playing here," Glover said. "It's kind of target golf, but I've always enjoyed coming here."
Jordan Spieth remained 8 under in his season debut, shooting even-par 71.