Whine/Whistle.
 

Hey y'all at speeds above 60kms I start to hear a whine, actually it sounds more like a whistle coming from the center console area maybe center dash area. If It I driving a consent speed it is not that loud much but if I press on gas pedal of take my foot of gas pedal it gets a lot louder, I'm positive it is not coming from any wheel. It almost sounds similar to a vacuum leak but I know I dont have one. Also I have my front shaft removed and I have the CDL engaged. Any Ideas.

A vac leak will go away on pedal to the metal, as vac drops. Vac is greatest when coasting at speed. So we agree on not a vac noise. So that leaves things like transfer case.

what do you suggest I check with the transfer case.

Fluid level. Have you changed it in recent memory? Use a thicker fluid (85W140)?

changed out t-case fluid. whistle still there. still there.

I have a 2003 discovery SE7, I have the same issue, the vehicle whistles when under acceleration. It does not whistle when I lift off the accelerator. Please tell me if you ever resolved your issue and if so what was the result? Thx

For those interested, I took the 2003 Land Rover discovery to rover doctor in Martinez California. He diagnosed the whining as the U joints in the front driveshaft. The original equipment you joints do not come with grease fittings. He installed a new driveshaft with greaseable U joints for $500 including parts and labor. Also, it fixed the "clunking, jerking" that I was feeling when the transmission was under load. This took him only 30 minutes. I watched, it would be very easy remove/replace at home. If you have a local machine shop that can press the ujoints you could do the job for parts only ($60 estimate plus labor of approx $150).

My problem ended up being a whine from the stereo.

My Disco has what I would call a 'belt squeak' once you get up to speed and let off a bit on the accelerator. Shifting into neutral makes it go away, doesn't do it when at a stop light. U-joints don't have any slop in them but I'm thinking they may be grooved inside the caps. Rear rubber bushing looks good, no signs of falling apart.

1997 132,000 miles (if that matters)