Dale Earnhardt Jr. reveals what led to retirement from NASCAR in new book

Dale Earnhardt Jr. details his racing career and what forced him out of the car in his upcoming book, "Racing to the Finish: My Story." Jared C. Tilton/Getty Images

In 2017, Dale Earnhardt Jr. surprised the NASCAR world when stock car racing's most popular driver announced he would retire at season's end. Many were shocked by the decision because Earnhardt had fought so hard to make it back after missing the second half of the 2016 season because of concussion-related symptoms.

Now Earnhardt has chronicled that entire experience -- the accidents and injuries that forced him out of the car, the depth of his struggles during rehabilitation, the comeback and the decision to retire -- in a new book, "Racing to the Finish: My Story" (Thomas Nelson), co-authored by ESPN senior writer Ryan McGee.

"Racing to the Finish" will be released Oct. 16 and is available now for pre-order. Here's an exclusive excerpt, followed by a Q&A between Earnhardt and McGee.

McGee: I will ask you the same question now that I asked you when we first sat down to talk about this in January. Why did you want to write this book?

Earnhardt: To help people. That's really it, first and foremost. When you get hurt, like breaking your leg or something, there's a tried-and-true map. Your leg did this and the bone did this and a million people have already been through this, so here's the road map and there you go. You know what you've gotten into. You probably know someone who has been through it already and you know what's happening and what's going to happen. But when you are suffering from a concussion, it is nothing like that. It doesn't make sense. How you feel doesn't make sense. If your brain is struggling, then every other part of you struggles, too. It's scary as hell. Then you go ask someone who has suffered before, like you would for any other injury, but people's experiences with head injuries are so varied, one size doesn't fit all. So, that talk might not help. Then you go try to research it and there's so much out there, it's overwhelming. So, that doesn't help, either. The science changes so fast, what we know about the brain, that your regular doctor might not have the latest information and misdiagnose you. That happened to me. So, I really wanted to lay out my experiences and the mistakes I made and ultimately the help I got and let people out there know, "Hey man, you don't have to suffer like I did. This can be fixed."

McGee: That first time we met about this, I was all prepared to dig into a lot researching of dates and crashes and asking you how you felt after each one. But then you airdropped me these notes that you'd taken on your phone that went back years. Those notes really became the backbone of the book.

Earnhardt: [Laughs] Yeah, I remember. And I was nervous to show them to you. I kept those in secret. Really no one had seen them outside of [my wife] Amy and my doctors until I gave them to you.

McGee: For me, as someone who has covered your entire career, especially the two times you were forced out of the car and your comebacks and all of that, when I was reading your notes about how you felt, really any time you had any sort of hit on the track, I realized that I thought I knew it all but I knew nothing. Sunday smacked the wall, Monday felt dizzy, Tuesday felt drunk, Wednesday felt better, and then the next weekend you'd go out and get a top-5 finish. Over and over again. For years. I was stunned at how far back they went and how often you had written these diary entries.

Earnhardt: It was like therapy for me, keeping those notes. It was the only place where I could really be honest about how I felt. But that also really made me worse in the long term. Because what I know now that I didn't know in 2014, '15, '16 was that whole time, the stress and anxiety of keeping it all a secret, the chemistry that comes with those emotions, it made my symptoms way worse. The people I am hoping to reach with this book are the people who are out there in the same situation I was in. They feel awful, but they don't want anyone to know, so they keep it to themselves. They try to tough it out. Meanwhile, not only are they feeling bad because they aren't seeing a doctor, the stress and anxiety of keeping the secret is keeping anything from healing like it should.

McGee: Why did you try to tough it out?

Earnhardt: Because I'm a race car driver, man. That's what we do. We wrote about that a lot in the beginning of the book. Every professional athlete plays though injuries and pain, but race car drivers have always been the guys who take it to the greatest extreme.

McGee: Ricky Rudd taping his eyelids open ...

Earnhardt: Guys racing with broken legs and arms and all of that stuff. It sounds awesome. And it is. But it also creates the kind of mindset where, even when you know you really need help you don't get it. That's showing weakness, man. Race car drivers don't do weakness.

McGee: But you don't have any problem revealing weakness in this book.

Earnhardt: It's not weakness, though. It's just me being too stubborn to get help. And that's not just a race car driver problem. The people I want to reach out to and help are the guys working construction or a kid who got hurt playing soccer or a mom who got into car accident driving home from the grocery store. When I would go see [Dr.] Micky [Collins] at the UPMC [University of Pittsburgh Medical Center], there would be dozens of patients there and I would be the only athlete in the room. The pro athletes receive all the attention, but he sees thousands of patients and almost all of them are just regular folks who suffered a head injury doing what they do. They didn't hit the wall at Kansas at 190 mph, but they are hurting every bit as much as I was.

McGee: So, do you harbor anger at racing for what you've had to suffer?

Earnhardt: No. No. No. I love racing. I always have and I always will. But racers need to be smarter about how they protect themselves. People will see in the book how many times I suffered a hit and didn't feel right and did nothing about it. That was my fault. When I finally was forced to get help, it saved my life. I'll always be angry at myself for not doing it sooner. We need to make sure that, going forward, racers don't make that mistake. I have talked to so many racers since I had my issues, guys who are retired and guys who are still out there, and I tell the same thing. If you need to take time off and get better, do it. I have given Micky's number out more times than I can count. If there's something a racetrack or a race team or NASCAR itself can do to make it better, then do it. Keep up to date with the science. Use my experiences. They all have my phone number. I hope they know they can call me. Just like I hope they read this book and think, "Damn, I don't want to be like that guy." Learn from me.