Buick 2001 LeSabre Owner's Manual page 258

6. Start the engine and let it run until you can feel the
upper radiator hose getting hot. Watch out for the
engine cooling fans.
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 DEX
through the filler neck until the level reaches the
base of the filler neck.
R
-
COOL coolant mixture
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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