Do not attempt to drain or refill the Lightning's coolant system on your own. This system is complex and integrated with the battery's thermal management, and improper handling can cause serious damage to the vehicle's expensive components, potentially voiding your warranty.
If you suspect a problem with your Lightning's coolant system (leaks, unusual noises, overheating warnings), contact your nearest Ford dealership or a qualified electric vehicle repair center immediately. They have the specialized equipment, training, and proper coolant to service the vehicle safely and correctly. Attempting to do this yourself is strongly discouraged.