GMC T-Series 1999 Owner's Manual page 170

3. Fill the radiator with the proper DEX
coolant mixture, up to the base of the filler neck.
(See "Engine Coolant" in the Index for more
information about the proper coolant mixture.)
5-22
5. Put the cap back on the coolant recovery tank, but
R
leave the pressure cap off.
-
COOL
4. Then fill the coolant
recovery tank to
COLD FULL.
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