I've attached picture steps below for your Ford truck on how to remove and replace the thermostat including the placement of the gasket- O-ring. Hope this helps and thanks for using 2CarPros.
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May 10, 2021 at 10:35 AM
Repair Safety Notice: This information is for general instructional purposes only. Vehicle repair can be dangerous. Verify all information, follow manufacturer service procedures, use proper tools and safety equipment, and consult a qualified repair shop when needed.