[jsrail]

Our 2002 Expedition Eddie Bauer 4.6L 2WD dropped oil pressure last night while my wife was driving home from my son's swim lesson (about 3-4 miles). The oil light went on then off and on but it made no sounds so she drove it 2-3 miles to about a mile from our home when the truck shut itself down. I went down to meet her and started the truck, (which started right away) and she sounded a bit noisy like low oil, but in 10 seconds the noise cleared up and it ran smooth with oil pressure at 3/4 of the gauge (where it has always run). I checked around the engine bay and no oil anywhere and none on the street and then shut it down. So I decided to try and drive it the 1 mile home, started it up and it showed 3/4 gauge oil pressure and a quiet motor. Right before I got home the oil pressure dropped to zero and I shut it off coasting to the front of our house.

Any ideas? The noise when the oil pressure showed zero it what really worries me.

[Kruser]

What is the service history of this vehicle and what type of oil filter does it currently have? Could there be sludge plugging up the oil pickup tube?
If it was mine, the very first thing I'd do is drop the oil and filter and get a new filter on it. Carefully inspect the old oil filter for visual defects and replace the filter with a new one. When I say filter, I mean a quality filter like a Motorcraft, a Wix or a Purolator. Any brand of filter could possibly have a defect, so I won't comment on the quality of the orange-colored filter. Motorcraft, a good choice for your vehicle, can be purchased in any WalMart store and you know you are putting on a good quality filter. Replace your oil (only because the filter is already off and it may have puked it's guts) with the proper weight specified for this engine. 5W-20, correct? Also inspect the factory oil sender unit. Is it leaking or have a loose connection? Sometimes when the oil gauge mistakenly drops to zero, the brain can hear all kinds of imaginary rattling. If there is any question about the oil sender, replace it with one from your Ford dealer. They are cheap.
After all this has been done and if there are still problems, hook up a mechanical gauge to it. If there are problems at this point, it will probably be time to pull of the oil pan and look for the culprit.

[jsrail]

The oil filter was a Wix and its changed regularly (every 3-3.5K miles) in the 20K miles we've putt on it. Can't say anything about the previous owner's habits though, we bought it second hand. I took it to a shop referred to me and they say they checked the pressure sensor and it was good, hooked up a mechanical oil pressure gauge and said the oil pressure was going up and down just as I noted. He flushed the oil system and put new oil and filter on it (nothing suspicious in the old filter he said) and that seemed to fix it. He drove it 5 miles and the oil gauge was normal (3/4 gauge) so he called us and said it was fixed. I drove it the 4 miles home, and then another 5 miles the next day when the oil gauge went up and down again, then stayed down for 30 seconds and I shut it down and had it towed home.

The shop claims that there is some noise in the front of the engine and said it needed a new timing chain.

Not sure what to do next, the shop said they get 13 hours to drop the oil pan and then I may as well put a used low miler engine in it.

I guess I could have it towed to Ford and just have them diagnose it for me?

Any further thoughts guys?

Thanks.....Jay

[Dominick]

You may just have a clogged oil pump screen but before tossing a bunch of money at itI'd check the bearings in it also.

[jsrail]

I keep hearing shop owner tell me how terrible the 4.6L Ford motor is and, at least around here, are very hard to come by because so many people are having to replace their own 4.6L's.

I'm wondering if it's even worth it to keep our '02 Expedition since every shop is telling me I need another engine, that the timing chains are making a lot of noise and the oil pressure problem is still there. I only consider it because its a nice looking truck with $700 of new tires we had to install and I can't afford to be buying another new car or truck. I am disabled and just don't want another monthly payment. eBay has rebuilt 3yr warrantied engines for around $1,600-2,000. All the shops around here want at least 13hours labor just to drop the pan! Is there another 4.6L which is not known for big problems from other Ford cars and trucks that would go into our '02 Expedition?

Not sure what I should do and am looking for any suggestions that I can ponder.

Jay