I drive a 2004 F-150 Supercab with a 4.6. It has 47,000 KM on the truck. I took it for an oil change last week and the mechanic noticed a large amount of white substance underneath the oil filler cap. There was a little bit on the last 2 oil changes however we thought it was from the moisture not being burned off inside the engine. I only drive about 5 mins to work each day and the truck is being shut off before it is actually reaching normal operating temperature, thus we thought any moisture would not be evaporating. This was the first oil change since December and I live in Nova Scotia, Canada where theres lots of moisture and cold. Another point of concern is the mechanic said that my coolant was down about a litre, however I don't remember the last time it was even checked, so who knows how long it took to go down that much. Anyways, I'm wondering if anyone else who drives so little has similar problems. I'm really hoping it is not a head gasket. I've changed the oil, topped the coolant and put some coolant dye in the rad. I'm going to see what happens in the next few weeks. The engine seems to be as good as it ever has. Unfortunately no warranty left...

Any comments, please let me know

 

its normal. its just moisture in the crank case. if you take it for a good long drive it wont be there.

 

Yep, condensation. No worries.

 

There's quite a bit there and I have taken it for long drives. Doesn't seem to matter. After I clean it out, it seems like it comes back right away. Could it just be lots of moisture?

 

When gasoline burns the carbon combines with oxygen and makes mostly CO2. The hydrogen combines with oxygen and makes WATER. With a little blowby, moisture (white stuff) could form on the fill tube, especially in the frozen north.

 

I've had this once. Since then I always make sure she warms up to normal op temp.
https://www.f150online.com/forums/20...ne-normal.html

 

That's typical of older Fords, I have an 85 and my oil filler cap has the exact same stuff, kinda gooey white residue, not an excessive amount, but just a little bit, if it's a LOT then you might wanna get it checked out, otherwise, like everyone else said, just moisture

 

As long as your oil looks normal and not milky, you are fine. If water was getting into the oil, you would know it.