REZCOV

Hi,, I've a Toyota Runx its 4wd,, 2003 model.... There is a vibrating sound coming from the front left side of the wheel when driving above 30kph. The vibrating sound usually comes when turning the steering even slightly on the left side I've changed the whole hub, drive shaft, & Diff also. The sound is still there. Can it be the gearbox now??? Any help will be appreciated.