ARD178

hi i recently bought a subaru wrx 2005 , and the gear box had been running with almost no oil on it , i few days ago raced two friends and it started to sound rare and it became difficult to go from 5 gear to 4 gear, after this race i checked the oil and realize that it had almost none, immediatly changed the oil and put 75w90 sinthetic new oil but, the damage was done already and i want to buy a new gear box. and this is where i need your help guys.

i found a gear box from a 2007 wrx with this code ty754vg7aa-t2 this gearbox will fit my 2005 wrx? and also would i need to change anything? my car has a push clutch, and i have no idea of what is the differential front or back.

Also another important question , i´m runnnig xxr 527 wheels 17 x 8.25 +25 in the front and 17 x9.75 +35 in the back with pirelli 225/45r17 tyres , i read that this car can take a 3% difference between tyres but i don'T know for shore if it is ok. any help you guys can give will be apreciated.

ARD178

i am been reading a bit could the problem of my gear box be the oil change? i put a 75w90 ultralub GL5 OIL .

could this be the problem? and a i may not need to change the gearbox?