Subaru Repair: whining in drive line, wheel bearings, subaru forester

Question
hey there i own a 2000 subaru forester gt, beautiful car goes gr8 and sounds awesome, i bought the car in november last year and have had no problems till i drove it for about 2400ks and started getting a loud whining noise. i am an ex mechanic but have had no experience working on AWD vehicles I have pin pointed it to the front end its a constant noise and does get louder at higher speeds, i have checked diff oil and is full. i have checked both wheel bearings and replaced rhf but noise still there. A few guys i work with are also ex mechanics and we do fill it is the diff but any real way of being 100% ?  any help with this problem will be helpful.
Btw the car is in Australia whether this may be differnet in any way.

Answer
Hi Bayly,

I am not sure what I can do for you, noises just aren't something I can address from here for you, if the wheel bearings have been checked by a pro, that really only leaves something in the front differential or transmission as the culprit, but I caution thats not a task for a laymen.

Justin

www.allwheeldriveauto.com