Why would the coolant be empty in your van when you have levels checked every 3000 miles?
Coolant should not be empty after 3000 miles. If your coolant is empty, there may be a leak in the cooling system. It's important to have the cooling system inspected by a qualified mechanic to identify the source of the leak and have it repaired. Driving with a low coolant level can cause the engine to overheat, which can lead to serious damage.