take the rad cap off and let the engine idle like that for about 10 mins or so with the heat on full blast....and rev the engine occasionally

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2021 F150 5.0 Screw

Past:18 F150 2.7, 16 F150 5.0, 14 F150 5.0, 07 F150 5.4, 03 Ranger 4.0

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