mine whines, sounds like an aeroplane taking off sometimes, but im still averaging high 20's, from other ppls posts and knowledge, its a very rare thing for a diff to pack up dispite these whines, but spose its always peace of mind. and ive senn them on the bay and on ere going for £20 sometimes, good luck mate

but perhaps try topping the diff up with oil and see how the whine drops and the mpg rises 1st
