The pop four-piece have finished recording their follow-up to 2008's Radio:ACTIVE and already chosen which songs will make the final tracklisting.
Taio Cruz has produced two tracks for the album - whose title has yet to be announced - with US producer Dallas Austin helming the rest of the record.
"We may have some additional production to do. There's half of it we haven't heard completely finished," drummer Harry Judd told Digital Spy.
"We've recorded most of it and left it with Dallas. He kind of works his magic with it and puts his synths on. So far the songs we've heard back we're really happy with."
However, despite working with a pair of R&B-oriented producers on the album, the band insisted that they have not abandoned their old sound entirely, describing lead single 'Party Girl' as its most "extreme" track.
"There are a few [songs] on there that, if anything, are more old-school McFly than we had on Radio:ACTIVE," said Judd.
Singer/guitarist Tom Fletcher added: "There's a lot of variety. Some songs are more soulful and sexy, and others are more ballady."
McFly release 'Party Girl' on September 6.
> Click here to watch our video interview with McFly