Johnson, driving the No. 84 Chevrolet for Legacy Motor Club, of which he is co-owner, ended up with the fastest average speed (194.225 mph).
While drafting together late in the 50-minute session, Johnson, Chase Elliott, Ricky Stenhouse Jr. and Alex Bowman posted the top four speeds.
“It’s my first weekend in this car. It’s Todd (Gordon, crew chief)’s first weekend working on the Next Gen car. First time we’ve all worked together,” Johnson said. “We’re going through quality reps right now.
“There are a lot of aspects to this that are new but I’m very proud of everybody at Legacy Motor Club and the effort they put into this. It’s so fun to get out there and mix it up.”
Aric Almirola and Joey Logano, who won Thursday night’s 150-mile qualifying races, ended up fifth and sixth-fastest, respectively.
Rounding out the top-10 were Chase Briscoe, Kevin Harvick and Zane Smith.
Among those drivers who ran at least 10 consecutive laps, Briscoe had the fastest average speed (192.001 mph). He was followed in that category by Logano, Bowman, Stenhouse and Almirola.