Allright, my mom's expedition has the 5.4 in it. It has a little over 80,000 miles on it. We change oil every 3000 or so. Whenever this thing gets to 3000 miles or close to it, it require oil. I happened to be home this morning, and my mom said she started it up and it made a clattering noise, so she turned it off. I went out and pulled the dip stick and it was dry. I am pretty sure there was some oil in it, but it was not enough to register on the stick. I put 2.5 qts in it. The last time she had her oil changed they said there was no oil in it, and that they couldnt work on it. There are no oil leaks on the driveway, so if it is leaking, its burning off. It doesn't smoke either. If someone can shed some light on where the hell 2.5 qts of oil is going after 2500-3000 miles, id really appreciate it. Otherwise, it runs fine, no odd noises, it seems to have all its power, and it gets about 12mpg.

Any info is appreciated!

 

I know it's obvious, but oil can only leave an engine a couple of ways. It leaks out or it's burned.

Since you said there is no oil on the driveway, that eliminates excessive dripping. But it could still be leaking out while it's being driven? but still, 2.5 qts every 3k is alot. You'd see oil residue someplace, and I'd think it would drip after so long anyway.

That leaves it being burned. I know you say it's not smoking, but I can't think of anything else.........

One way to know if it's being burned is to check the plugs. Maybe look at the tail pipe to see if it has oil residue or is really dark. These engines run pretty lean, and I've noticed that mine does NOT have that much "soot" inside the tip.

All these are just guesses........ A place to start at any rate.

 

Yeah,

youd think that amount of oil would be pretty obvious. I haven't looked under the hood yet. Next time i get a chance ill check it out. She took it to the ford dealer, and the best the mechanic could do was fill it and say, "Keep an eye on the oil level". Ill have them check the tailpipe though. I kinda think that if is was LEAKING, even if only when driving, sooner or later, it has to come out and on to the ground. So i guess the only other option is burning, which I guess would be rings?

 

Rings and / or the valve guides are the only places I can think of. Gaskets of course, but then you'd see it leaking!!

You may want to check the PCV on the pass side valve cover. Make sure it "Rattles" when you shake it. Also check where that PCV hose connects to the valve cover and the manifold. Look for execessive oil residue.

Wonder if it could be leaking from the rear main seal into the tranny? Maybe check the tranny fluid dip stick and make sure the fluid is NOT really dark. It should be a nice clear red color.

 

I had the same problem it was my passeger side head gasket leaking wasn't hitting the pavement because it would drip on the converter and burn off this is also a common problem with 5.4