Chevrolet 1996 Tahoe Owner's Manual page 233

6. Start the engine and let it
run until you can feel the
upper radiator hose
getting hot. Watch out
for the engine fan(s).
7. By this time the coolant level inside the radiator
filler neck may be lower. If the level is lower, add
more of the proper mix 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. Be sure the
arrows on the pressure cap line up like this.
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