My fiancees grandparents bougtht us a 2002 outback as a wedding gift. Ive had 4 subies before this one and never a big problem. but this one has a whine whenever we give it gas and the whine gets louder as we go at higer speeds but will stop if put in nutrel or if we let off the gas. Her grandpa says this is the rear differential and not to worry about it.I didnt listen and wanted to fix it so I dont have stress or to hear the whine anymore. but I found some threads on here where that happened and then the transmission blew.
my question is can I replace the differential without replacing the whole transmission??? and if so how much will it cost for a shop to do this??? and will driving it this way blow the transmission? also if we do replace the differential and the whine is gone are we good,or should i still be worried about the tranny? this is scary for us because we dont have money to get a different car or replace a whole transmission. the subie has 140k on it and is in emaculate condition. the check engine light has come on,I'm guessing due to this issue since everything else seems great.