I want to get my 3.31 stock gears out and want to put in some 4.10s. I am getting a tune from breenspeed but I think the 3.31 are going to hurt my performance. Should I change gears? Or keep the 3.31? I dont go to track but I cruise around town a lot and love the extra power. What kind of gain will be there with tune and 4.10s? My 2007 gt has 38,00 miles, Will bearing be ok? Rear END?