Okay my dad and I are having this long debate about the rear end on my car. My car has the stock 13 in wheels on it that are soon to be changed to 15x8's on the back. Now my major concern is traction, getting it to hook up at the track is very important for getting my times down. Now my dad is talking about sending the car to the shop to get the differintial seal changed because it's leaking, and while it's in there he wants to have gear's put in it. My preference is around 3.73's. NOW he belives that if we put 15 inch wheels on the back then we have to put lower gears in it to improve the way its hooking up at the track. But my car doesn't even have trac-lok It's a one wheel wonder. So I've been trying to tell him 15's and lower gears aren't going to help much if the power isn't getting put down through both tires. So he thinks that we don't need to worry about getting trac loc right now because the gears are going to fix a lot. I say Trac loc or nothing at all. If we don't do both at the same time, I don't want gears in the car until it has the locker. Please someone please help me explain this!