Have a 2004 expy E.B. I bought the truck with 50,000 miles and since the I have put on 35,000 miles. All my oil changes are done with Sythectic Oil and i noticea foamy residue under the cap for the oil resorvoir. The last oil change, I felt I was getting robbed becuse they charge me extra to flush it out. But one of my friends to a look at it today and said it was condensation under the cap. My question to guys is this normal for Syn. oil to act this way, or do I have a big problem? I installed a K&N air intake system and flowmaster cat bak. Plus I has a program for superchips. Thanks for some info.

 

That foamy resirue is usually a very bad sign! It is an indication of moisture in your crankcase which usally a sign of leaking gaskets or a cracked casting. Take it to a radiator shop and have them pressure test the cooling system, if it will not hold the recommended pressure you are facing some expensive repairs to correct the problem.
Good luck with it.

 

i use syn. oil in my 98 windstar, my wife drives it on a lot of "short"
trips, 3-5 miles at a time,when it gets really cold outside it gets a little light brown to
a tan color slime inside the oil fill cap. the engine never gets hot enough to evaporate
off the moisture as the oil warms up. if your leaking antifreeze internilly you should see
the fluid level go down in your overflow tank.