Gearbox Noise

[eddie230668]

Avensis 1.8GS VVTi 2001 120,000 miles

A few weeks ago a noise developed, and had it confirmed by a mechanic that it was the gearbox.I have now resigned myself to the fact that i need a replacement. What puzzles me though is that the noise is not constant all the time. When i start up first thing in the morning i can hardly here the noise for the first 3 miles or so before it becomes evident. It then differs during the day, depending on the distance traveled, and sometimes gets really bad. The noise is like a very fast clicking at slow speeds, developing into a constant dry bearing sort of growl at high speeds. I have checked the oil level which is full, although i dont know when it was last changed. At least not during the 40,000 miles which i have done. I thought i would post on here just to see if anyone else has had the same problem, and did changing the oil make any difference, as temperature is obviously affecting the noise.