Gayle King on 'Third Wheeling' Oprah Winfrey and Stedman Graham's Vacations Since 1994 (Exclusive)

Gayle talked to ET about her and Oprah's three-part series, 'OG Chronicles: Joyride,' and their long-lasting friendship.

Gayle King and Oprah Winfrey are back on the road 15 years after their infamous cross-country trek! ET's Rachel Smith spoke with Gayle about her and her lifelong friend's new series, OG Chronicles: Joy Ride, where the pair embark on a multi-stop adventure through Santa Barbara, California.

"We're calling it a homage to the road trip. So what we did, we did a joy ride around Santa Barbara where she lives, and we surprised Oprah insiders," Gayle explained to ET. "So this was really funny, they would be on the phone, they would be on Zoom, talking to somebody from our staff asking questions about being a part of Oprah insider and we would be at the front door going, 'Hello, open the door, hello.' And you could see them go, 'Wait, somebody's at the door, hold on a second.' And they'd open their door and there we are. That was great fun."

While on the road, the best friends reminisced about their last road trip and all the vacations they've taken together, especially the ones where Gayle ended up being the third wheel for Oprah and her longtime partner, Stedman Graham's, vacations.

"I'm a proud third wheeler," Gayle admitted. "I make no apologies for that. I got divorced back in 1994 and I've been their third wheel ever since. The good news is that Stedman is always very welcoming, so it never occurs to me when she says, 'We're going to so and so,' I'm like, 'When?' It doesn't occur to me that I'm not invited. But throughout the years, we've gone on some great trips together. And that's not gonna change."

During their drive, the pair touched on how Oprah's decades-long relationship with Stedman has factored into their friendship, and why for Oprah, Stedman liking Gayle was a non-negotiable: "Husbands and boyfriends come and go. Best friends last forever."

"Oprah came to my house after my favorite daughter, Kirby, was born and she was wearing a T-shirt that said, 'Husbands come and go, best friends last forever,' and I went, 'Whoa, why are you wearing that T-shirt?' She didn't even realize, she said she didn't even realize she had it on, but there is some truth to that," she said of their unbreakable bond.

Gayle continued, "When you have a best friend, you really are there through thick and thin, and that's not always true with husbands and spouses or you know, co-workers, anybody in your life, but when you have a true best friend, it really does. It is something that really is a lifelong thing."

And as her lifelong friend, Gayle is taking the wheel on their little joy ride this time, as driving is definitely not one of Oprah's favorite things.

"She ain't changed. She doesn't like to merge, she doesn't like to get on the highway, she doesn't like to parallel park, man, she doesn't like to change lanes, all the things that come with...driving!" the CBS Mornings co-host revealed. "I really enjoy driving. I actually do, but what I really like is the rule [that] if you're behind the wheel, you get to control the radio!"

Oprah took to Instagram to share a then and now photo of her and Gayle to celebrate their joy ride adventure, 15 years after the famed talk show host had sworn off road trips altogether. 

"@gayleking said it best: I don’t like to merge. I don’t like to park. I don’t like to pass cars. I don’t like highways. So I never thought I’d go on another road trip again—but here goes Gayle convincing me to join her on another adventure…15 years later," Oprah wrote. "This time around we surprised @oprahdaily Insiders at their homes, shopped with @katyperry to prep for @kirbybump’s first baby, and I survived Gayle’s singing yet again 😂 Visit or tap the link in my bio to watch the first episode of The OG Chronicles: Joy Ride 2021. The next episode comes out next Thursday, September 16!"

Watch these best friends hit the road on their three-part series, debuting Thursday on Two more episodes are set to drop Sept. 16, with the finale hitting Sept. 23.