The curb weight of a 2013 Dodge Grand Caravan is 4510 pounds.
Curb weight is the total weight of a vehicle with standard equipment, all necessary operating consumables (e.g., motor oil and coolant), a full tank of fuel, while not loaded with either passengers or cargo. (Wikipedia)
The gross weight is 6050 lbs.
The gross weight is the maximum operating weight/mass of a vehicle as specified by the manufacturer including the vehicle's chassis, body, engine, engine fluids, fuel, accessories, driver, passengers and cargo. (Wikipedia)
You can drill down under the New or Used Cars tabs above and once you get to the make/model you are researching, you can find the weights under the Exterior section under Reviews & Specs.