i don't quite know how to explain my driving experience with my 96 discovery it has the 5.0 and an automatic. i know for a fact that its front swivel joints need repaired but i don't think that is where that noise is coming from. i also know that the transmission cooler lines and the engine oil cooler lines are leaking and need repair. i'm going out on a limb when i say i think the noise is coming from leaky seals but it could be i guess i don't know. the last thing it could be is the transmission or gearbox itself. another thing is the vacuum bulb that controls the cruise control is broken. it does get louder as i put more pressure on the throttle and the noise is constant.

 

I would start checking fluid levels

Mine has a whine cause I need to swap out the power steering pump, they are known to go bad

Only things that should whine are trans, PS pump, maybe alternator

I reiterate check the fluids in diffs transfer case etc, its easy to burn up these things from little leaks, transfer case will lock up

 

turning the wheel creates its own noise, so the power steering pump is a highly likely culprit i'm not really driving it much right now so i'll start investigating that as i go on and keep fixing my disco.

 

Video the sound helps

 

I've had an alternator and power steering pump whine. The last time I heard a similar noise, however, it turned out to be a failing belt tensioner. It gave out at lunch one day throwing the belt off. I managed to make it home before the truck overheated too bad. Easy fix, but I'll throw that out as a possibility.