How do you change the coolant on a 1998 gmc vandura?

To change the coolant on a 1998 GMC Vandura, start by allowing the engine to cool completely. Locate the radiator drain valve at the bottom of the radiator, place a drain pan underneath, and open the valve to let the old coolant flow out. Once drained, close the valve and fill the radiator with a 50/50 mix of fresh coolant and distilled water, ensuring to also fill the overflow reservoir. Finally, run the engine to circulate the new coolant, check for leaks, and top off the coolant level as needed.