Ram has built a number of 1500s, 5.7 hemi's with the new 8spd trans. Some or most of them have the 3.21 gears. The tow rating is about 2,000lbs less than the same truck with 3.55s regardless if the tr...
it would depend on what you are going to use the truck for!!!!!
if your trailer is close to the max tow load of the truck, then go with the 3.73.
if fuel mileage in your main goal, then go with the other ratio.
my dodge diesel has the 3.73 ratio, but it has 310hp and 610# of torque, so with the 3.73 it can pull anything that I have ever hooked to it with no problem.
your truck will have more hp, but when you really load up and take off up a hill, you need torque.