Hi, I have a defender 300tdi 110, it has over the last 100 miles developed a transmission noise that sounds like I have off road tyres on . It only does it under load, the faster I go the more it whines, if i come off the throttle it stops , does it in low box as well , sounds like a badly worn wheel bearing, have looked at ujs, greased them, they all seem okay, changed oils about 1000 miles ago,gears all change good, wonder if its front diff, any help would be greatly appreciated, thanks .