My 53 plate Mondeo TDCi 130 has developed an odd whine while driving. The noise is road speed rather than engine speed related, i.e. when the noise is heared, depressing the clutch and allowing the engine to reach idle speed does not affect the noise, nor does engaging neutral and releasing the clutch. I had initially suspected a wheel bearing, but the noise doesn't change while driving round corners and is more of a whine than the usual wheel bearing rumble. In case the two are connected, my clutch has begun to slip slightly if I accelerate while the turbo is boosting hard. The brakes are not binding and in any case, applying them does not alter the noise beyond it reducing with road speed. Gear selection is nice and smooth. I am hoping this may be something 'simple' like a drive shaft bearing but I have a niggling fear you may tell me you suspect the gearbox.
it could be a number of things, i would need to test drive the vehicle