Franco hit a two-run homer in the first inning against Jordan Zimmermann and another two-run shot off the Tigers righty in the fourth.
"They have a lot of young guys on that team and a lot of free swingers," said Zimmermann. "It's a little more difficult to set them up when you know they're going to be hacking."
Franco has four home runs this spring.
"A little bit," Franco said, asked if he feels locked in offensively.
Zimmermann allowed five hits, four runs and one walk and struck out three in 3 2/3 innings. Phillies right-hander Aaron Nola allowed four hits, two runs and one walk in 2 2/3 innings. He struck out four.
Nola gave up a two-run home run to Tigers catcher James McCann in the third inning.
"The more at-bats you get, the more locked in you feel," McCann said. "The big thing is just seeing pitches and seeing different pitchers."
Tyler Collins singled to score a run in the fourth inning against Phillies left-hander Daniel Stumpf to give the Tigers a 3-2 lead. After Franco's second homer, the Tigers tied the game in the fifth when Nate Schierholtz scored, despite being caught in a rundown at third base.
Darnell Sweeney put the Phils ahead in the sixth when he scored from second on an Angelys Nina single and a Tigers error.
Up next for the Tigers: The Tigers travel to Kissimmee, Fla., to take on the Astros in a 1:05 p.m. ET game on Friday. Michael Fulmer, ranked as Detroit's No. 1 prospect by MLBpipeline.com, will be on the bump as the starter. He hasn't allowed a run in four innings of work this spring. Listen to the game live on Gameday Audio.
Up next for the Phillies: Phillies right-hander David Buchanan will start Friday afternoon against the Braves in Lake Buena Vista, Fla., at 1:05 p.m. ET. Right-hander Charlie Morton had been scheduled to start, but he is out with the flu. The bug scratched Jeremy Hellickson from his scheduled start Wednesday. Listen to the game live on an exclusive webcast.
Todd Zolecki is a reporter for MLB.com. Read his Phillies blog The Zo Zone, follow him on Twitter and listen to his podcast. This story was not subject to the approval of Major League Baseball or its clubs.