I have a 2000 F150 with a 5.4 Triton engine. I went to one of those quicky oil change places. The kid took one look at the underside of my oil cap and said, "No use changing your oil, you have a blown head gasket, because of the funky white stuff here on the bottom of your oil cap". Can anyone tell me if this is true? I havent suffered any loss of power, or any other abnormal conditions with the engine, so Im curious whether this guy was off base, or what. Thanks.

 

Did you actually have the oil changed since? Have you looked at the oil coming out?

What the kid thinks he sees is a milkshake like, ligth brown emulsion that you create when coolant is mixed with motor oil. The mix usually gets created by coolant getting into the crank case through a defective head gasket. This can also happen at intake gaskets and timing cover gaskets, depending on the engine.

You should pull your engine oil dipstick and check if you see milkshake emulsion instead of oil. If you do, see a milkshake stop driving the truck immediately. The emulsion has no lubrication ability and your engine (bearings) will be toast in a matter of miles!

Of course this isn't the only symptom for a blown head gasket, but it can be the only one visible if it goes a certain way.

What the kid could also have seen was some additive in the engine oil that you might have added? Sometimes also dyes that are put in the oil to check for leaks can turn the oil filler cap underside into a strange looking color...

If you have coolant go into your crankcase, you should also see a coolant loss in your coolant system. Also, sometimes the oil can go the other way, so you might see oil in your coolant!

If you are not sure what is going on, bring your truck to the dealership for the oil change and checkup. The damage you might create by leaving this unattended can be huge.

Hope this helps,

George

 

I would bet that you drive your truck on short trips to work. If that is the case you will get the funky white stuff. BUT, that is not a indicator of a blown head gasket. A sign maybe but not a indicator. He was full of it.

I really doubt that you have blown gasket. Really doubt it.

 

As Dan implied, short trips will not burn off condensation in the oil pan, causing a milky white emulsion to form on the inside of the oil cap. Is your truck overheating? Is it blowing coolant out the overflow tube? Does your exhaust have a steamy quality after warm-up? Is the engine down on power? If the answer to all questions is "No". I doubt you have a problem.

Bear in mind that in some cases, a wide gulf of knowledge stands between the kid at Jiffy Lube and a certified tech.

 

OK, thanks a million George, Dan, and Paul. Your information was helpful and greatly appreciated.
Believe me, the next time I get my oil changed, it will be at a certified Ford Dealership.
Thanks again! :-)