GMC 2005 Savana - Manual (Page 269)

3. Fill the radiator with the proper DEX-COOL ®
coolant mixture, up to the base of the filler
neck. See Engine Coolant on page 5-22 for more
information about the proper coolant mixture.
4. Then fill the coolant recovery tank to the COLD
FILL mark.
5. Put the cap back on the coolant recovery tank, but
leave the radiator pressure cap off.
5-31