Depends on what engine you have.
For a 2002 six cylinder engine the capacity is 4.5 liters.. that's if you change the filter. I would imagine the 2003 was similar.
The 4 cylinders capacity was actually more although I don't recall what it was.
Answer: For a 2003 Dodge Grand Caravan, the manufacturer's recommended engine oil viscosity is 5W30. The engine oil capacity is 5.0 quarts (this applies to both 4 cylinder and V6 models.)
According to the 2003 Mercury Grand Marquis Owner Guide : With engine oil filter change ( 6.0 quarts / 5.7 liters of engine oil )
The maximum cargo capacity of the 2003 Suzuki Grand-Vitara is 50.2 cu.ft..
The maximum cargo capacity of the 2003 Dodge Grand-Caravan is 167.9 cu.ft.
The maximum tosing capacity of the 2003 Dodge Grand-Caravan is 2000 lbs..
The maximum cargo capacity of the 2003 Jeep Grand-Cherokee is 71.7 cu.ft..
The maximum tosing capacity of the 2003 Suzuki Grand-Vitara is 1500 lbs..
The maximum tosing capacity of the 2003 Jeep Grand-Cherokee is 5000 lbs..
The oil capacity of the 2003 Kia Rio engine is 3.6 Quarts.
under the oil
I have a 2003 Freelander and at the dealer they say the oil capacity is close to 6.5 Litres.
The 2003 Jeep Grand-Cherokee has 38.3 cu.ft. of cargo capacity with all of its seats in place.