Ewan McGregor

Rodney Copperbottom (voice)

Halle Berry

Cappy (voice)

Greg Kinnear

Ratchet (voice)

Mel Brooks

Bigweld (voice)

Drew Carey

Crank (voice)

Amanda Bynes

Piper (voice)

Robin Williams

Fender (voice)

Jim Broadbent

Madame Gasket (voice)

Stanley Tucci

Herb Copperbottom (voice)

Dianne Wiest

Mrs. Copperbottom (voice)

Jennifer Coolidge

Aunt Fanny (voice)

Paul Giamatti

Tim the Gate Guard (voice)

Natasha Lyonne

Loretta Geargrinder (voice)

Dan Hedaya

Mr. Gunk (voice)

Jay Leno

Fire Hydrant (voice)

James Earl Jones

Voice Box at Hardware Store (voice)

Stephen Tobolowsky

Bigmouth Executive / Forge (voice)

Alan Rosenberg

Jack Hammer (voice)