I read these motors, timing chain guides(plastic) fail. The pieces break off and get sucked into oil pick up. If this happened, this motor is toast. I would look for a wrecked, truck with a good motor. You can buy the whole truck and sell the other parts. Or use your parts to fix the wrecked one. $3-4K is too much to spend for a 03. Don't throw good money for bad. Used Expeditions are easy to find. I would move on.