Cole Custer was fastest in the final Xfinity Series practice Friday at Dover International Speedway.
Custer led a Stewart-Haas Racing sweep of the top two spots with a speed of 151.292 mph.
Teammate Chase Briscoe followed at 150.558 mph.
Gragson recorded the most laps in the session with 75.
Custer had the best 10-lap average at 149.737 mph.
Briscoe had the fastest lap with a top speed of 152.394 mph.
Zane Smith recorded the most laps in the session with 39.
The session was red flagged once for Gray Gaulding having a mechanical issue and possibly putting down fluid.