Technical 2007 19d SX Doblo Cargo, gear box excentric wine slow road speed?

[Edtheted]

My gear box/transmission (84k miles from new) makes an excentric wine at slow road speed almost like a diff. Bearing, is it a common problem with these boxes, what is my best option to sort it please?

 

[bugsymike]

My gear box/transmission (84k miles from new) makes an excentric wine at slow road speed almost like a diff. Bearing, is it a common problem with these boxes, what is my best option to sort it please?

Ideally, assuming plenty of oil in gearbox I would get it supported on a garage ramp with both wheels at normal road height, possibly supported on lower suspension arms (not hanging down as will cause drive shaft noise/issues) then run vehicle up to the speed it makes the noise and use a stethoscope/long screwdriver to locate where noise is exactly.
Hopefully this way is safest.
Generally if diff pinion gears the noise will change from over run to accelerating.
Wheel bearing noises usually can be located by the change as cornering.
You can get a noise from o/s drive shaft support bearing, though usually constant regardless of cornering etc.
Sometimes if a gearbox bearing you can feel a higher temperature through the casing on the dodgy one.
I did have a 05 Doblo 1.9 with noisy gearbox, where the first motion shaft bearing failed this would be noisy in neutral revving the engine, though that one had over 200k miles on it.