hello ,
I have a 52 plate is200 and am suffering from gearbox noises , the gearbox is whiney in most gears especially 1 - 3, it sometimes clunks into 2nd and I am getting a bass droning noise whilst in 4th gear between 50 and 60 mph which is most noticable when the acellerator is released , this disappears when the clutch is pressed. I also get heavy vibration in the gearstick in first gear when accelerating.
I have had lexus stockport recently look into this and the changed the gearbox oil and diff oil and added what they called a bung to the gearbox to reduce or eleviate the bass droning problem , this bung is what they descibed as a counter ballance weight attached to the back of the gearbox.
None of these solutions eleviated the problems and I am now awaiting Lexus is suggestion to resolving these problems
cheers