Hello, I am John, a Ford dealer technician.
I hope I can help solve your problem quickly and accurately.
To change fluid in your explorer you will need to drain it first. Now remove the pan anc replace the filter. Now you reinstall the pan and remove the center plug from the main plug. Now you will need a special adapter and a tool to push the fluid back into the trans. You should put 5-6 quarts in. Start the truck and let it get warm. Once it is fully warmed up remove the fluid pusher tool and let the fluid drain from the small plug. Once it stops draining it is up to the full level. If you go to a hardware store you can find a hose barb that will go into that plug to fill it. Then you will need something to push fluid in. You can't just hook a hose to a bottle. You need a pressure filler.
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