Ok so last week I was about to take a drive to Albuquerque and I checked the oil before I left. I added a half quart and when I pulled the oil cap, it had.. like kind of a brownish white foam. Not alot, but just a little bit, inside the oilcap. I wiped it out and replaced it. I checked it today, and nothing new has come up. Since I've had my 4runner its burned a small amount of oil between oilchanges. I am not missing any coolant. Any clues as to what the white junk was?

 

coolant ?

 

Sounds like it might be time for a compression test.

 

How does one perform a compression test?

 

http://www.misterfixit.com/dyncompr.htm

 

how cold is it where you are? What sort of driving have you been doing?

Short drives in cold weather will result in the white sludge under the oil cap. This CAN be normal, as condensation has not burned off.

 

A leak down test is more effective, IMHO, for finding a possible HG failure... Ask for a "leak down tester" at your autostore. Harbor Frieght carries a cheap version that does seem to function ok.