Larson clocked in with a lap of 168.177 mph. Blaney was second fastest with a lap of 167.530 mph.
Championship contender Erik Jones was third fastest with a lap of 167.328 mph, Alex Bowman was fourth fastest at 167.069 mph, and another Chase contender, Daniel Suarez (166.795 mph) rounded out the top five.
Elliott Sadler, also competing for the championship, was 11th fastest at 165.822 mph, while his teammate and the final championship contender, Justin Allgier was 16th fastest at 164.609 mph.
During the 1 hour, 25-minute session, three cars found trouble.
Sadler hit the wall in Turn 4, damage his Chevrolet. Tifft also hit the wall in Turn 4. Ryan Blaney scraped the wall at the entry to Turn 3.