Van Pelt shot 6-under-par 66 and Sluman shot 5-under 67.
The round was suspended because of heavy rain late in the day, with both leaders at 11-under 133 through 36 holes.
Tiger Woods is 12-under through 12 holes of Friday's round.
Harrison Frazar (64) and Jim Furyk (68) are tied for third place at 10-under 134. Joe Durant, Brett Quigley, two-time defending champion Vijay Singh, first-round leader Mike Weir and Woody Austin at 10-under on the course.
The cut will be determined after the second round is completed.