I'm new here. I own an 04' Lightning and an 04' Expedition (5.4).
My Expedition has ~44K on it. I changed the oil 500 miles ago and there was a thick yellowish goo under the fill cap and inside the fill tube. I cleaned it off and 500 miles later it is back. What is causing this? Is my engine on it's way to an early grave?
I would greatly appreciate any advice.

 

The term "yellowish" throws me off, but it kinda sounds like you have some water in your oil. That's usually what causes "goop". What kind of oil are you running, and what have you done that's "unusual" since your last oil change? additives? weather?

 

I guess it's more of a cream color.
I have been using 5w-30 for all my oil changes. I noticed before my last oil change and it's still there. I have not put in any additives and the weather hasn't been any different that normal, maybe some colder, but nothing unusual. I did have to add a little bit of coolant also. I din't notice anything unusual when I changed the oil. Could coolant be getting in there somehow?

 

Yeah, probably. It's odd, I don't really know what to tell you, it's such a new vehicle, it's hard for me to believe. I'd hate to tell you to tear your motor down. Because, I am no expert in 5.4 mechanical design. I've never had any problems with mine. Just give this post a day or two and see what some of the "old timers" have to say about it. We even have a few ford mechanics here, and they might have seen this before on your vehicle. Did you try a search? Maybe there's some old info... I just don't remember reading anything recently about this...

 

If the oil on the dipstick looks good, I bet it's just condensation build up. Especially with the colder weather. The engine heats up and cools down, producing condensation on the bottom of the oil cap. I get the same thing on the bottom of my filler cap also. And the coolant level stays normal. Condensation gets my vote!

 

What kind of driving are you doing?
Sounds like condensation.
Short trips, cold weather, in and out of garage?
If your engine is not getting up to optimum temperature then the water condensation can't "evaporate" out of your oil.
If not that then keep an eye on how much coolant you are adding! Hopefully you don't have coolant leaking into you oil.

 

condensation

 

Thanks for the inputs. It just started when it got really cold, so hopefully that is it. It is used for mostly short trips, in and out of garage, and my wife's rough driving. I'm just surprised I haven't ever noticed it on any of my other vehicles. I ckecked my Lightning too and there was nothing, but I drive that ~60 miles/day.

 

It's condensation...there was a big huge thread about it somewhere on here not too long ago... It was on my oil cap when I changed my oil about 2700 miles ago...

 

You may want to check your PCV valve to make sure you have air moving in your crankcase. I had a generic PCV valve on for a few weeks and I had that cream color on the bottom of the oil cap. I put in a Motorcraft PCV and a few weeks later checked it again and it had almost cleared.

 

Makes me wonder.....