Hi, I am thinking about buying a 1985 GMC Jimmy,its four wheel drive V6 automatic,ok so the lady im buying it from says there is vacuum problem with the transmission and that the car wont shift because of it(only does 30mph cuz it wont shift). could that really be the problem if so how much will it cost for me to fix it my self an what parts do i need? please name what else it could be an how to fix it.thanks
