GMC 2003 Savana Van Owner's Manual page 278

3. Fill the radiator with the proper DEX-COOL@
coolant mixture, up to the base of the filler
neck. See Engine Coolant on page 5-24 for more
information
about
the proper coolant mixture.
4. Then fill the coolant recovery tank to the COLD
5 . Put the cap back on the coolant recovery tank, but
FILL mark.
leave the radiator pressure cap off.
5-35