The oil capacity for a 1999 Dodge Grand Caravan SE depends on the engine. There were a few different engines offered that year. To know for sure, you need to check your owner's manual or look at a sticker under the hood (often near the oil filler cap).
However, generally, the 1999 Dodge Grand Caravan SE engines held between 4.5 and 5 quarts of oil. You should not simply assume this is the correct amount for your vehicle. Always consult your owner's manual for the precise amount.