To be absolutely sure, you should:
* Consult your owner's manual: This is the best resource for the precise location on your specific model year.
* Use a repair manual: A Haynes or Chilton manual (or a digital equivalent) will have diagrams and instructions.
* Search online forums: Search for your specific Navigator year and model ("Lincoln Navigator 2023 air suspension pump location," for example) on forums like NavigatorChat.com or others dedicated to Lincoln vehicles. Pictures from other owners can be very helpful.
Because it's under the vehicle, you'll likely need to get underneath to locate it. Be aware of hot components if the vehicle has been recently driven.