Well, while having my oil changed, some condensation was discovered on the oil filler cap. I've heard this is often a sign of a head gasket failure. However, I have not discovered any water/coolant on the dipstick. It also seems to be running at normal temp., and it's not using any coolant(that I can see, anyways). I've heard that driving short distances can cause condensation to build-up, and I do have a fairly short commute to work(10 mils one-way), but the engine always reaches operating temperature.

I have heard of head gasket problems on the 5.4L. I've also heard that a clogged PCV valve can cause condensation. Thankfully, I did buy an extended warranty with the truck, so the repair won't put me in the poorhouse.

Now, I'm wondering what to do. Should I take it to the shop immediately, or keep driving it while keeping an eye on the condensation?

My truck is a '99 with the 5.4L, and 74,500 miles.