NEWTON, Iowa — John Hunter Nemechek raced to his second straight NASCAR Camping World Truck victory, taking the lead with his six laps left Friday night at Iowa Speedway.

Nemechek took four new tires during the final caution. The gamble paid off, as he passed leader Johnny Sauter soon after a restart.

The 20-year-old Nemechek raced to his fifth career victory, driving the No. 8 Chevrolet for his father, former NASCAR Cup driver Joe Nemechek. He won last week at Gateway in Madison, Illinois.

"We knew that we were going to have a good truck here," Nemechek said. "The truck wasn't the greatest from the start of the race. The track kept changing a lot...somehow it all worked out in the end."

Sauter, the series leader, led 72 laps. But his team's choice to stay out on old tires at the end of the race cost him dearly.

Brandon Jones was third, followed by Grant Enfinger and Christopher Bell.

Bell led a race-high 99 laps, but he dropped to 12th after pitting under caution for new tires just before the final stage.

Though Sauter and Bell had the two most dominant trucks of the race, Nemechek and his team mastered the late-race strategy that is typically crucial on Iowa's short oval — which has gotten rougher and bumpier over the years.

"That was the only call to make," Nemechek's crew chief, Gere Kennon, said about the decision to take four tires. "It was the thing to do. It just suited our style this week

Chase Briscoe, who had finished second in back-to-back races, passed Sauter with 18 laps left and seemed assured of his first career win if the race stayed caution free.

It didn't, because Matt Crafton got clipped and sent into the wall just a few laps later.

The drivers on the lead lap were then faced with a choice. Sauter's team chose to stay on the track and hope that his tires had enough left to hold off the field.

"In hindsight, we should have put tires on but we didn't," Sauter said. "Not a whole lot of deliberating."

Briscoe also fell back on the final restart. He finished seventh.

Noah Gragson, who was sixth, won the pole for the second time this season and led for just 16 laps before Bell slipped past him. Bell went on to claim his fourth stage win of the season.

Bell continued to dominate in the second stage, maintaining a strong lead over Briscoe. But the race's first flag came just before the end of the second stage when Mike Senica spun off the track.

Sauter, with the fresh tires he could've used at the end of the race, pushed Bell hard on the restart and eventually overtook him.

Ben Rhodes and Kaz Grala then got collected in a multi-car wreck that knocked out Grala — who was eighth in points entering Iowa — for the rest of the race. Sauter hung on to win the stage.

Despite the loss, Sauter increased his points lead over Bell to 42.