While driving and about to shift into two or more gears you will hear a noise coming from the transmission this problem happens because the input shaft bearing or the main shaft bearing of the transmission is damage.
Possible cause of noise when shifting in two or more gears
1) Transmission has damage input shaft bearing2) Transmission has damage main shaft bearing
It is very difficult to determine what causes the transmission problem not unless the actual transmission is inspected therefore the cause of the problem mentioned on this article is just a common possibilities and can only be confirmed once the transmission is brought into shop.
The most common cause of noise on the transmission when shifting into one or more gears is a damage input shaft bearings or damage main shaft bearings these two components rotates at all speed inside the transmission, because of this two rotates at all speed it will creates noise when either of the two is damage.
How to correct noise when shifting into two or more gears
First thing to do is to determine what is the real cause of the noise when shifting and you can only do that if the transmission is opened up for inspection. With that said no other option but to bring the car to a shop that specialized in transmission job, explain to the mechanic what you suspected as the cause of the problem, probably the mechanic will inspect the transmission to determine cause of noise when shifting.
Before you agree to tear down your car transmission you may try to consider having a second opinion coming from other shop to see if the transmission is need to be opened up, and of course be financially ready because this type of job is expensive because of the work involve, but if your car is still under warranty then you are covered and nothing to worry because the car manufacturer will shoulder all the expenses.