Steve Briscoe
Lifetime Supporter
The last two times I've changed the oil in my daily driver, there has been a white grease like substance in the oil filler cap and inside the neck of the oil fill tube. I use Mobil 1 and a Mobil 1 filter and change oil every 5,000 miles even though the extended formula advertises it will go a lot further than that. When changing the oil, I did not find any water or other type of separation in the oil. My '99 Jeep Grand Cherokee has 210,000 miles on it and stills runs strong. It uses about a quart of oil every 4,000 miles. I've seen some pretty nasty things on oil caps or in oil pans but nothing like this. What is it? Thanks!