Gearbox/engine noise

[Danh200484]

Hi
I wonder if anyone can shed some light on a issue im having on my Citroen Xsara Hatchback 2003?
when i'm driving along the car is making a whirring sound in every gear, but when you drop the clutch or coast out of gear or even on idle the noise stops.
The noise has started getting louder over the last week, and i'm just trying to pin down what to check before i take it to a garage and waste money on diagnosing the issue and the repair bill.

The car was MOT'd 2 weeks ago. and no mechanical issue was brought up, as at first i thought it might have been a wheel bearing or something like that.
I have been told that it might be the clutch release bearing? could this possibly be the issue or would it more than likely be something else in the gearbox? It does not make the The reason i think its gearbox related is due to the fact it only happens when driving and changing gear, get up to 70'ish and the noise stops or the roads noise masks it.

if anyone can help out that would be fantastic.

Thanks

[RichardW]

Wheel bearings tend to be noisy all the time, and are related to road speed.

Input side bearings in the gear box will only be noisy when the power is on, and will be related to engine speed. Output side bearings will be related to road speed, and may be quieter when off the power.

Release bearing will only be noisy when the clutch is pressed, and will be related to engine speed.

If this is a 1.4 then the MA gearbox fitted is prone to lunching the differential, this noise is road speed related and often gets worse when cornering.

[xantia_v6]

It might be worth checking the gearbox oil level.

[Danh200484]

Wheel bearings tend to be noisy all the time, and are related to road speed.

Input side bearings in the gear box will only be noisy when the power is on, and will be related to engine speed. Output side bearings will be related to road speed, and may be quieter when off the power.

Release bearing will only be noisy when the clutch is pressed, and will be related to engine speed.

If this is a 1.4 then the MA gearbox fitted is prone to lunching the differential, this noise is road speed related and often gets worse when cornering.

Thanks for the reply, Yes it is the 1.4 but i don't know if its the MA Gearbox or not.
if it did turn out to be one of the above what would you say the best option is new gearbox? or 2 matches in the tank seeing as the cars not worth as much as the repair bill lol...

[flying clutchman]

If it's a 1.4 it will be the ma gearbox. Pretty easy to change, depends whether you think it's worth the effort

[Zelandeth]

I have had clutch release bearings on the way out rattle or hiss at idle (I assume they were loose on the gearbox input shaft so were rattling around) but went silent as soon as you put any pressure on the pedal - this was on Skoda's which had a reputation for having clutch release bearings made of cheese - and the above symptoms in both cases for me were very quickly followed by the usual horrible noises usually associated with a failing release bearing...so didn't take long in my case to figure out what it was.