The Pacers came back from a five-point deficit after one period to lead by as many as 17 in the final quarter en route to their third straight win.
Granger made 13-of-15 free throw attempts while Darren Collison added 20 points, nine assists and six rebounds. Grander and Collison teamed to score 28 of Indiana's 31 points in the third period.
Minnesota got 21 points and 17 rebounds from Kevin Love, but fell for the second time in five games. The Timberwolves shot only 37 percent from the floor.
Indiana played without George Hill, who suffered an ankle injury on Tuesday against New Jersey. Hill is averaging nine points a game.