Crew members perform a pit stop on Kyle Busch's car during the NASCAR Daytona 500 auto race at Daytona International Speedway in Daytona Beach, Fla., Sunday, Feb. 26, 2017. (AP Photo/David Graham)
FILE - In this Wednesday, Feb. 22, 2017 file photo, Dale Earnhardt Jr. answers questions during an interview at NASCAR Daytona 500 media day at Daytona International Speedway in Daytona Beach, Fla. Dale Earnhardt Jr. is often the center of attention at the Daytona 500, where he has won twice. But things are different this year. All those cheers for NASCAR’s most popular driver have been joined by fears about his health. He missed the last half of last season because of a concussion. He says he is fully healthy, but the real test will be the first head-jarring crash in his car. The season-opening race is Sunday, Feb. 26, 2017. (AP Photo/John Raoux, File) **FILE**
Chase Elliott answers questions during an interview at NASCAR Daytona 500 media day at Daytona International Speedway, Wednesday, Feb. 22, 2017, in Daytona Beach, Fla. (AP Photo/John Raoux)
Joey Logano answers questions during NASCAR Daytona 500 media day at Daytona International Speedway, Wednesday, Feb. 22, 2017, in Daytona Beach, Fla. (AP Photo/John Raoux)
Danica Patrick shows off her driving shoes during an interview at NASCAR Daytona 500 media day at Daytona International Speedway, Wednesday, Feb. 22, 2017, in Daytona Beach, Fla. (AP Photo/John Raoux)
Dale Earnhardt Jr. answers questions during an interview at NASCAR Daytona 500 media day at Daytona International Speedway, Wednesday, Feb. 22, 2017, in Daytona Beach, Fla. (AP Photo/John Raoux)
Brendan Gaughan makes comments at NASCAR Daytona 500 media day at Daytona International Speedway, Wednesday, Feb. 22, 2017, in Daytona Beach, Fla. (AP Photo/John Raoux)
Jimmie Johnson, left, talks with a team member outside his garage during a practice session for the Clash NASCAR auto race at Daytona International Speedway, Friday, Feb. 17, 2017, in Daytona Beach, Fla. (AP Photo/Terry Renna) **FILE**
Driver Bobby Gerhart stands by his car on pit road before his qualifying run for the ARCA 200 auto race at Daytona International Speedway, Friday, Feb. 17, 2017, in Daytona Beach, Fla. (AP Photo/Terry Renna)
Driver Bobby Gerhart stands on pit road before his qualifying run for the ARCA 200 auto race at Daytona International Speedway, Friday, Feb. 17, 2017, in Daytona Beach, Fla. (AP Photo/Terry Renna)
FILE - In this June 30, 2016, file photo, Dale Earnhardt Jr. gestures as he speaks during a news conference before the start of a NASCAR Sprint Cup auto racing practice at Daytona International Speedway, in Daytona Beach, Fla. NASCAR has a new sponsor, a new format and a familiar face this year in its bid to rebound from declining ratings and attendance. The next 11 months will show if Dale Earnhardt Jr., Monster Energy and different rules can provide the needed jolt.(AP Photo/Wilfredo Lee, File)
FILE - In this July 1, 2016, file photo, Dale Earnhardt Jr. prepares before the start of practice at Daytona International Speedway, in Daytona Beach, Fla. Earnhardt, who missed the final 18 races of last season because of a concussion, has been medically cleared to return next year. Hendrick Motorsports announced Thursday, Dec. 8, 2016, that Earnhardt will take part in the season-opening Daytona 500. (AP Photo/Wilfredo Lee, File)
In this Feb. 23, 2014, photo, Dale Earnhardt Jr., left, celebrates in Victory Lane with teammate Jeff Gordon, right, after winning the NASCAR Daytona 500 Sprint Cup series auto race at Daytona International Speedway in Daytona Beach, Fla. Gordon will get one more shot to win in Indianapolis this weekend when he replaces Earnhardt Jr. in the No. 88 car. On Wednesday, July 20, 2016, Hendrick Motorsports announced that Earnhardt would miss the next two weeks as he continues to battle balance issues and nausea. (AP Photo/Terry Renna, File)
A member of Kasey Kahne's crew displays a U.S. flag in his hat band on pit road before the NASCAR Sprint Cup Series auto race at Daytona International Speedway, Saturday, July 2, 2016, in Daytona Beach, Fla. (AP Photo/John Raoux)
Jimmie Johnson puts his helmet on to re-enter his car during final practice for the NASCAR Sprint Cup series auto race, Saturday, May 14, 2016, at Dover International Speedway in Dover, Del. (AP Photo/Nick Wass)
Denny Hamlin celebrates in Victory Lane after winning the NASCAR Daytona 500 Sprint Cup Series auto race at Daytona International Speedway in Daytona Beach, Fla., Sunday, Feb. 21, 2016. (AP Photo/Terry Renna)
Denny Hamlin smiles during an interview after he won the Sprint Unlimited auto race at Daytona International Speedway, Saturday, Feb. 13, 2016, in Daytona Beach, Fla. (AP Photo/John Raoux)
Chase Elliott laughs with crew members in Victory Lane after he qualified for the pole position in the NASCAR Daytona 500 auto race at Daytona International Speedway, Sunday, Feb. 14, 2016, in Daytona Beach, Fla. (AP Photo/John Raoux)
Jimmie Johnson sprays sparking wine as he celebrates in Victory Lane after he won the NASCAR Sprint Cup series auto race, Sunday, May 31, 2015, at Dover International Speedway in Dover, Del. (AP Photo/Nick Wass)
Jeff Gordon prepares to go out on the track during a practice session for the NASCAR Sprint Cup Series auto race at Daytona International Speedway, Friday, Feb. 13, 2015, in Daytona Beach, Fla. (AP Photo/John Raoux)