In case you haven't watched the video yet, milky sludge on an oil cap is simply an indication of water condensation in an engine. At the worst, it means you've blown through a head gasket and coolant has been ruining your engine for some time. Simply check your oil on the dipstick. If it's not milky too, then you're probably just having problems with living in a cold area, or your taking too short of trips for the water to boil off in your engine.
Despite no milkiness under my oil cap, and generally driving in a warm environment, this explains why there is a general brown tinge to all the parts inside of the engine in my 1999 Chevy Prizm. I should have been increasing my oil change interval.
I think I do a lot to prevent issues, always using quality synthetic motor oil like Mobil 1 or Castrol with Syntec. When these synthetic motor oils are the extended mileage type my oil looks pretty clean up to 5k to 5.5k miles, but when I get synthetic that doesn't have the "extended" design I only get about 4.4k miles out of the motor oil. (These synthetic motor oils are rated at 15k and 7k respective to my 5.5k and 4.4k mile synthetic motor oil change intervals.) I'm basing these decisions by how dark the oil gets.
It's all those short trips. I'm building up water, and therefore acids because of living in smaller towns since 2005. The metal of my engines in a Metropolis looked much better. You know, where I was usually driving at least 23 miles to work, and I bought much more used cars and it was a colder area too.
Short trips really are hard on cars. I never fully believed it, but "proof is in the pudding"! Just don't eat it! lol
I guess at 130k miles of having even my reduced "extended" synthetic motor oil change intervals, I should have stayed under 4k miles the whole time (car has 170k miles plus now).
Check out one of my other articles about synthetic motor oil. This article gives some answers to the questions. Why synthetic? How does it help with my cars miles per gallon?
by AutoBravado
