For the 3800 engine, remove both block drains (knock sensors).
Filling Procedure Notice: DO NOT use cooling system seal tabs (or similar compounds) unless otherwise instructed. The use of cooling system seal tabs (or similar compounds) may restrict coolant flow through the passages of the cooling system or the engine components.Restricted coolant flow may cause engine overheating and/or damage to the cooling system or the engine components/assembly.
Notice: The Low Coolant warning/indicator lamp may come on after this procedure. If after operating the vehicle so that the engine heats up and cools down three times, the Low Coolant warning/indicator lamp does not go out, or fails to come on at the ignition check, and the coolant is above the full cold mark in the reservoir, refer to Low Coolant Warning/Indicator Lamp. If at any time the Temperature warning/indicator lamp comes on, immediate action is required. Turn OFF the engine and allow the vehicle to cool. Do not remove the coolant recovery reservoir cap at this time.