METALLICA Warms Up For SONISPHERE In Back of Truck (Video)

The members of METALLICA warmed up for their headlining appearance at the U.K. edition of the Sonisphere festival on Friday, July 8 by running through a few tunes in the back of a truck outside the press area. Check out a short video clip below.

Although METALLICA is currently completing work on a surprise collaborative album with Lou Reed, the band is also about to start writing songs for its 10th studio effort on its own. Producer Rick Rubin, who worked with the group for the first time on 2008's "Death Magnetic", told Billboard that he recently met with drummer Lars Ulrich and will return to San Francisco sometime in the next week or so to sit down with the whole band and "explore what the focus is going to be this time around."

Rubin offered a hint of how that initial meeting with the band will go: "I'll ask a lot of questions and we'll probably listen to some of the riffs they've been writing. And usually I'll hear something that will sort of indicate the direction and then we'll talk about it from there."

Rubin did not give a timetable for when he thought METALLICA might begin recording.

The band revealed last month that the "secret recording project" it was working on in May was a collaborative album with Reed, the legendary singer and former VELVET UNDERGROUND frontman.

The project had apparently been in the works since Reed and METALLICA performed together at the 25th anniversary of the Rock And Roll Hall Of Fame at Madison Square Garden in October of 2009.

METALLICA has not indicated when or how the yet-to-be-titled album will be issued.