I spend all my time towing cars /trucks, we have a 97 chevy 3500HD 2wd and you have to hook up to a 3/4 ton or better to feel the diff. in any major way, fuel economy wise the trucks diesel and gets 10 mpg empty or towing. climbing the grade I mentioned earlier is about the same you loose 5 mph tops coming up. Same when towing with my HEMTT in the army you had to be towing a 2500 golloan fuel truck to notice any major diff. Now tow a jeep trialer behind a jeep and you kno the diff.
