Gas,
what does your trailer weight + mama bear's cargo list.
you need to have a good handle on this number before you go looking for a truck of any brand.
always seems like when water tanks and gas tanks are full + mama bear's stuff, the weight sure does mount up fast,
it's always best to load the trailer ready for the road, than have it weighed.
I have the 2500, 2005 model dodge Diesel and you cannot lockout overdrive on my model, you only have T/H, but it's been fine towing my trailer which only weighs around 7K.
Truck has plenty of power and T/H held the load back coming out of the mountain's.
however, I have been told with heavier loads, the T/H will not hold the load back, but that has not been a problem for me.
so, if you are going to tow near the limit of the dodge truck, you may want to invest in some type of exhaust brake, if the 2006 model does not have one.
good hunting, I have sure enjoyed my dodge truck,
I never owned a vehicle with that much hp and torque.