I need some assistance. My truck overheated and now there's milky oil in the valve cover. There's no milky oil in the oil pan and the antifreeze is like an oily color. I think it's a head gasket but I'm no expert. also the heat doesn't work. It blows cold.

 

Likely a head gasket or cracked head. Milky oil is not a good sign. Best of luck with it.

 

Where exactly is it milky? When gas burns, it turns into CO2 and H2O(water). When an engine is high mileage there is an increased amount of blowby past the rings and this blowby is CO2 and water. I've had an old Dodge that had the dipstick mounted in front of the engine and the air coming through the radiator cooled the dipstick enough that there was a milky substance in the dipstick tube. Not a problem. Short trips may not get the oil hot enough to evaporate the water in the blowby that partially ends up in the oil.

 

If the oil itself is not milky, it's most likely condensation due to cold and hot temp changes. Are there any bubbles in the radiator?

 

Do a hydrocarbon test on the coolant.

 

Also, clean/replace your PCV valve. If it is clogged, condensation does cause the milky residue. Carb cleaner works really well.

 

Not to hijack your thread but I am in a similar situation. I noticed my oil pan gasket was leaking when I dropped my front axle to do a 4wd repair. Since it's a piece of cake with the diff down I opted to replace it. I noticed a white milky film in the pan. Not much and had I not dropped the pan I doubt I would have ever seen it. My truck doesn't over heat and the heat works good. I do short trip driving. What are the odds it's just condensation and not a headgasket issue? The truck is a 2002 f150 with the 4.6 and 175k. Thanks

 

Probably just condensation, but you could do a hydrocarbon test on the coolant to make sure.

 

Yeah. I will probably do an oil sample. Were I work, there is a Fabco right across the street and they do all our samples. Might be able to get a discount. lol