I don't have any Dodge vehicles, but it should be in that owner's manual somewhere. Look for a specifications chart, either in the back of the book or try its index. More importantly, you need to identify your specific replacement plan. If you are planning on draining and refilling the transmission, you won't need the total fluid capacity, as you can only drain a fraction of the amount. A rough guestimate would be that you should only need 3 to 4 quarts for a drain and fill. Of course, you can use more than that if you use a more advanced method of replaceing the fluid.
Vic