I have spent weeks trying to find something similar to this problem and have looked at the car a few times but I am stuck.
Basically I will try to describe/detail the fault as best I can and I just hope someone out there will be able to pin point the cause [please not the gearbox!!]
2005 MINI COOPER PARK LANE EDITION WITH GETRAG 5 SPEED
This noise only occurs whilst the car is in motion.
Pressing the clutch in and out makes no difference.
Placing the car in neutral and switching the engine off whilst coasting makes no difference.
Using the brakes makes no difference.
Turning the car at speed appears to make a difference, the sound can become less loud.
Sometimes the noise disappears altogether, mostly just for 5 to 10 seconds or so but a few weeks ago it went away completely for 2 days before coming back. When it goes quiet all that can be heard with window down is a rubbing noise but this could be the front rotors/discs as I think they are slightly warped.
The gearbox operates flawlessly, very smooth in operation, no vibration, no grinding, clutch feels smooth.
I have performed a full gearbox oil change, drained entirely about 1.5 litres [should be 1.7 for 5 speed Getrag] but put 2 litres back in of thicker oil [85W instead of 75W] and added a whole tube of Molyslip. Driven for over 200 miles over 5 days and made no difference to the sound characteristics of the noise.
It is only noticeable from 20MPH upwards with the window open and no radio on. With the windows up and radio on it cannot be heard until about 35-40MPH. The sound can be heard best when driving alongside a brick/concrete wall with the window down and is VERY loud. It appears to sound as though it comes mainly from the LEFT HAND side of the car when sat inside BUT I have driven on the wrong side of the road against a brick wall with the drivers side window down and the noise could be heard almost as loudly as on the left hand side.
Now to describe the noise itself.
Imagine the sound of a piece of metal band/ribbon that has been attached at one end to a rotating shaft and the other 'flapping' end of the band/ribbon strikes against other metal objects as it is rotating creating a kind of metallic rattling/flapping noise. The noise is very uniform, it does not change in pitch or speed by itself, only the speed at which the car is traveling dictates this.
Have any of you experienced this??
I hope you can help