The new contract kicks in next season, with incentives that could push the total closer to $65 million.
Granger scored 33 points Wednesday night at Detroit in Indiana's season-opening loss to the Pistons after averaging 19.6 points and 6.1 rebounds last season.
Milwaukee center Andrew Bogut scored a five-year deal worth a guaranteed $60 million.
If there are no further deals before Friday's midnight deadline, New York's David Lee would rank as the most high-profile member of the class of 2005 not to receive an extension.
Denver's Linas Kleiza appeared close to an extension all week, but his agent, Bill Duffy, told the online edition of the Rocky Mountain News that talks have been abandoned.
"[Nuggets owner Stan] Kroenke decided [Friday morning] he wanted to keep some flexibility open and we don't disagree with that," Duffy told the newspaper. "We think that [Kleiza] has some options."
The sides were discussing a four-year deal in the $25 million range, but Kleiza will now become a restricted free agent July 1.
Marc Stein is the senior NBA writer for ESPN.com. To e-mail him, click here.