Lost here...I have a resonating whistle sound while I'm driving, it speeds up when I give it more gas and gets quieter when I let of the throttle can't wrap my head around what this is. Sometimes I will be off the throttle and it still makes the noise. Any ideas??

99' discovery

VIDEO: http://youtu.be/naegqE0HI2k

 

Does it make the noise when you aren't driving down the road and just rev the engine up slowly?

 

No it doesn't.

 

Did you check the vertical door window felt seals? They typically slide down and make noise because of the air movement.

 

If I'm reading correctly (which may not be the case due to the massive hangover I'm suffering from) it seams to be a drive train issue. The vehicle is still moving when he let's off the throttle.

Obvious checks have been completed? Driveshaft u joints, diffs and wheel bearing?

 

I'll have to check the bearings (it doesn't really sounds like bad bearings though) also just greased the drive shaft and replaced the diff fluid and transfer case fluid yesterday.

 

does it sound like drivetrain or does it sound like a body related noise>\

 

have you had a look around your exhaust manifold? my d2a had a whistle and it ended up being the manifold leaking after I had spent $1000s on changing things good luck

 

I'm guessing it's drive train but it doesn't seem very consistent. Sometimes are louder than others. I'm going to check the drive shaft again. Or maybe throw a GoPro under the body to see if I can pinpoint anything.

 

I first thought exhaust manifold when you said whistle, but watching the vid it's more a squeak or chirp I would say.

If drive shaft is greased, I would look at wheel bearings, although I have no experience of them with discos. Jack each corner and see if you have any odd wobble.

I've just replaced my guide pins in the calipers which cured a squeak I had. Kinda similar to your noise. Cheap, easy and another thing to tick off as 'done that'. I can almost imagine a slightly warped disc/rotor making that cheep noise, if the pins were bad. Any vibration with braking?