Why heavy Weight?
Drifter was partially correct, the heaver weight oil tends to leak less. But the main reason for the heavy oil is I live in Eastern Georgia. With temps in the 95+ all summer and me driving home in the highest heat and heavy traffic, I decided to run the higher viscosity oil. I have never added a oil cooler to any vehicle to help with the cooling so I just made this a habit. If I were up north, I would run a 10W-30 or 10W-40 since the temps are not as extreme.