Actually this will work for 2015+ 3.5 V6.

I watched YouTube videos on how to do this and thought it was crazy to try and contort my arm in the blind from under the vehicle to get the oil filter off.

Opened the hood and realized you can stand on a stool (I'm only 5'8"), reach down behind the radiator, and throw a strap wrench on the filter and pull it off. It's right on the front left side of the engine.

Easy, or at least not virtually impossible like the underneath method.

 

That's how I do it but now if there was only a way to keep the oil from running all over the place when you remove the filter. I've even tried having the rear tires up on ramps and it still won't run out the spout of that drip tray like it's supposed to.

This is the only vehicle I take in for an oil change.

 

I wad up a bunch of paper towels and put them in the drip tray.

Then I wipe down the tray with more paper towels sprayed with brake cleaner.

 

I basically did what jschira does. Next time thinking about putting a little 1" high platter down there to try and catch the oil. If you move fast you'll get just a little oil on the towels.

 

I don't have the 3.5 but it sounds like the same stupid oil filter location/tray as my 2015 F150. I built a oil catch that attaches to the back of my drip tray on the 150. I cut a quart oil bottle up so that it has a hook on it and it hangs off the aft side of the drip tray it catches the oil that comes off the aft side and I have my normal oil pan under the front side. After the oil drains out, I wipe down the tray and no oil mess on the floor.
If this sounds like what you have on the 3.5 let me know and I'll take some pictures.

We are looking at getting a 16-17 Navigator so I am trying to get schooled on the 3.5.

 

Yes Expedition and F150 3.5 EB is the same set up.