Ok. Next weekend, I'm planning on taking the quads out to the Hassayampa River bottom outside of Phoenix. We usually prefer to tow the quads using the Dodge 3500 with the Cummins. However, it doesnt seem like that will be an option. I've only towed with it once before. What is better O/D on or O/D off? Also, would I benefit from using the Selec-Trac in 4 Full Time?