Noah Gragson posted the fastest lap in the final practice for the Gander Outdoors 150 at Pocono Raceway with a lap of 168.732 mph.
He beat Myatt Snider (168.026 mph) by .224 seconds.
Cup regular Kyle Busch (167.255) landed seventh on the chart.
Brett Moffitt blew an engine late in the session. He was 11th on the speed chart at the time with a lap of 165.981 mph.
Ben Rhodes crashed in the final minute of practice after posting the eighth fastest lap of 167.094 mph.
None of the drivers ran 10 consecutive laps.
Lightning in the area paused on track activity after the trucks were able to complete only 15 minutes in the first practice session.
In the short amount of time trucks were on the track, Kyle Busch posted the fastest lap of 167.320 mph.
He beat Gragson (167.212) by .035 seconds.
Ben Rhodes (165.682), Todd Gilliland (165.615) and Grant Enfinger (164.760) rounded out the top five.
Because of the weather delay, time was added to final practice, which resumed following ARCA qualification. Times from the first 15 minutes were rolled into the final session.