Miley Cyrus sings 'We Can't Stop,' 'The Climb,' 'Wrecking Ball' on 'Carpool Karaoke,' rates career moments on 'how high' scale: Watch

Of course Miley Cyrus sang all the hits during her return engagement to "Carpool Karaoke." But just a few weeks after the singer appeared on the Apple Music spin-off version of James Corden's singing ride-along series with the entire Cyrus clan, Tuesday night's (Oct. 10) edition with Corden behind the wheel gave Miley a chance to not just belt "Wrecking Ball," but also reveal just how high she was when she filmed the video for her iconic hit.

"10... 10," she said without hesitation about where she was on 1-10 scale.

In keeping with her more serious persona these days, though, Cyrus also spoke to Corden about how her legendary twerk-tastic appearance at the 2013 MTV VMAs alongside Robin Thicke actually helped her transform into an activist. "I realized if that many people were going to talk about something that I did, or something that I do, then I should make it a good thing, and I should make it something that can change people's lives rather than be a controversial conversation that does nothing but become a fun Halloween costume for people," she said.

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"I think there was something when I first, you know, kind of stopped doing Hannah Montana... saying, 'I'm not that, I want you to know who I really am,' but I love that that was me and is me and is a part of me. And I think I've allowed that childhood self to shine through a little more because I'm not trying to run away from it, I'm down to embrace it. I think that's good for everyone should embrace who they used to be because it's made you who you are now."

It wasn't all serious topics, though, as Miley gladly pulled out her infamous wagging tongue to help Corden lick some stamps for some letters and share her terrible driving record, including wrecks in her own driveway and a recent windshield-shattering bang-up with a sound trailer on the set of The Voice. Of course they also harmonized beautifully on "We Can't Stop," "The Climb," "Party in the U.S.A.," a very emotional "Wrecking Ball" as well as "Younger Now" and "Malibu" from the singer's new album, Younger Now.

Miley also revealed what dog-related drama helped her work up tears for the "Wrecking Ball" video.

Watch the episode below: