'90 325ix whines at high speed from front under power

[canadiankid]

'90 325ix
5 Speed
246xxxkm or 152xxx miles
known issue is a torn cv boot front, driver, outer. Going to fix that soon. probably 500km on it since I bought the car like that.

So when I am driving along everything is fine, when I hit 90kmh(50mph) or more, whenever it is under power there is a whine from the front end. Not very noticeable, but I notice it. As soon as you let off the gas, it completely disappears. Actually, I would probably describe it as more of a groan. AWD is operational, all four tires spin. Happens in fourth and fifth. I don't drive that fast in third. Any ideas? Going to change out all the fluids soon too. Any help and tips on that would be greatly appreciated.

Thanks in advance.

[canadiankid]

Thanks for the info. Havent driven it in a week, just sprayed penetrating oil on the plugs, gonna change the fluid tommorow. Wouldve already done it, but I don't have metric allen key sockets. I know the back is 17mm, is the front one the same?

[nando]

AFAIK the front uses smaller sized allen sockets.

[canadiankid]

Yes, there was hardly any fluid in the front. Much quieter now. Thanks.

[canadiankid]

No big deal. My mechanic did it. I couldn't find metric allan keys as big as 17mm anywhere. I looked really hard.