Biffle regressed in 2006, missing the Chase for the Cup despite winning twice at Darlington Raceway and Homestead-Miami Speedway (both of which were tracks at which he had also won in the previous season). He finished 13th in the standings, third-best of the drivers not to qualify for the Chase. He also missed the Chase the following year, in a season marred by the No. 16 team's new primary sponsor Ameriquest Mortgage suffering financial difficulty and having to sell off a number of its race sponsorships. Biffle won only one race in 2007, at Kansas Speedway. As Biffle was doing burnouts on the track, third place Jimmie Johnson and second place Clint Bowyer accused Biffle of not maintaining speed under a final lap caution but this was denied by NASCAR who said Biffle had pace car speed.