hi, a friend of mine is selling his slightly used tires 315/70 17. is there anybody out there installed this tires or similar size on their tahoe 4x4 if so my question is will these tires rob on my fenders using an oem Z71 rims with leveling kit installed (front)? do i need to change the gearing and/or what changes should i expect if i decided to install these tires (in terms of gas mileage, speedometer, acceleration, etc.). thanks!