I have a 2005 Chevy Surburban 2 wheel drive 1/2 ton with a 5.3 L. motor. My truck currently has 3.42 gear ratio in it. I am towing a 32 ft travel trailer that has a empty weight of 7400 lbs. I am going to upgrade the diff. gears, however I can't decide between a 3.73 gear or a 4.10 gear ratio...