Next month, Tom Petty will bring Mudcrutch, his pre-Heartbreakers band, back into the studio for the follow-up to their 2008 reunion album. In a new interview, he talked a little about his plans for them and about the mysterious second disc of Wildflowers that's been in the vaults for 21 years.

Saying he has about four songs written for Mudcrutch, which included Heartbreakers Mike Campbell and Benmont Tench, he tells Rolling Stone that he's "frantically working on material for that right now, really over the past month. The good thing is that everybody brings in a song so I don't have to write 12 or something. But I'm working on it. Some of the most fun I have is those Mudcrutch sessions. It was just so much fun and I think that's one of the better albums I was ever involved in. I'm hoping it's something like that again."

As with the first, it will be recorded at the "big Heartbreakers club house out in the valley." But he's not sure if it, like the last effort, will take only 10 days to record. Still, after its release, they plan to embark on a proper tour, unlike in 2008 where they only played a handful of shows across California.

"I want to get over to the East Coast with it too," he continues. "Last time we were kinda under the gun because there was a big Heartbreakers tour coming up not long after that, so we didn't have a lot of time. We kind of just ran up and down the West Coast real fast and did a fairly long stand at the Troubadour. Those were really fun gigs. It's a totally different thing than the Heartbreakers. It's a different rhythm section. It's a different style of music."

Last month, Petty released a new song, "Somewhere Under Heaven," in conjunction with the Entourage movie, where it played during the closing credits. The track was recorded for 1994's Wildflowers, which will see a second disc from those sessions called Wallflowers: All the Rest hit shelves at some point in the future. But Petty is quick to point out that these aren't outtakes.

"The original plan was to release it as as the complete Wildflowers album with the original album and this," he said. "And Warner Bros. came back to us and said, 'Look, this is far too good a record to just send straight to the catalog racks. We're going to put it out as its own album.' I was behind that decision too. It's done and we're eventually going to put it out. It's just sitting there finished, so I'm waiting to hear when they're going to put it out."

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