DAYTONA BEACH, Fla. — Dale Earnhardt Jr. doesn't know when he'll end his winless streak, or how long it will take to turn around his horrendous season.

The only thing NASCAR's most popular driver — winless in 38 races — is certain of is that he's not strong enough to withstand another year like this one.

Earnhardt heads into Saturday night's race at Daytona International Speedway ranked 19th in the standings and still adjusting to a crew chief change six weeks ago that brought an emotional end to his long working relationship with cousin Tony Eury Jr.

As his struggles snowballed through April and May, it affected everyone in the tight-knit Earnhardt and Eury families.

"I can't have another year like this. I can't mentally. I can't physically. I don't want to put the people around me through this," Earnhardt said in a wide-ranging interview with The Associated Press.

"When we were really, really struggling, everybody in the family was upset. Crying and carrying on. All the women were crying, the men we're cussing. I'm serious. This is our family, Eurys and Earnhardts, racing is our life and it wears on all of them. We can't put anybody through this (stuff) again. We've got to get this right."

Stoic through the aftermath of his father's fatal accident in the 2001 Daytona 500, and steady as his popularity pushed him into rock star status, Earnhardt rarely gives a glimpse of any inner turmoil.

So when cracks in his armor began to show in late April, it slowly became clear to team owner Rick Hendrick he'd have to make the split that Earnhardt and Eury were too emotionally invested to recognize how badly it was needed.

Hendrick pulled the trigger following a 40th-place finish at Charlotte, replacing Eury with interim crew chief Lance McGrew and assigning additional personnel to Earnhardt's No. 88 team.

"I feel like we've let him down, maybe I've let him down, by not pulling the trigger earlier," Hendrick said. "For maybe his sake and Tony's sake. Both of those guys are going to be better off."

That's been evident for Earnhardt, who admits his confidence was shaken during the rocky first four months of the season. As Hendrick Motorsports teammates Jimmie Johnson, Jeff Gordon and Mark Martin raced their way into Victory Lane and contention for the Chase for the championship, Earnhardt couldn't keep pace.

He made rookie-like mistakes, struggled with his cars and led just 84 laps — the bulk coming at Phoenix when Eury used pit strategy to put Earnhardt out front for 63 laps. Through 12 races with Eury, Earnhardt had just three top-10s, and his season-best finish was second at Talladega, where he's "supposed" to be good.