2009 Hummer H3T Owner's Manual - Page 262
2009 Hummer H3T Manual
Page 262 highlights
5-26 Service and Appearance Care 5. Reinstall the cap on the coolant recovery tank, but leave the radiator pressure cap off. 7. By this time, the coolant level inside the radiator filler neck might be lower. If the level is lower, add more of the proper DEX-COOL coolant mixture through the filler neck until the level reaches the base of the filler neck. 8. Then replace the pressure cap. At any time during this procedure if coolant begins to flow out of the filler neck, reinstall the pressure cap. Notice: If the pressure cap is not tightly installed, coolant loss and possible engine damage may occur. Be sure the cap is properly and tightly secured. 3. Fill the radiator with the proper DEX-COOL coolant mixture, up to the base of the filler neck. See Engine Coolant on page 5-23 for more information about the proper coolant mixture. 4. Fill the coolant recovery tank to the FULL COLD mark. 6. Start the engine and let it run until you can feel the upper radiator hose getting hot. Watch out for the engine cooling fan.