just curious if anyone else has this issue. i went to add a quart of oil the other day, and saw some milky white stuff on the bottom of my filler cap. its also around the top of the dipstick tube. just curious if this is just because its at the entrances or whats going on. it has been snowing/raining pretty heavily lately and i have been putting a LOT of miles on her recently. if anyone has any educated ideas or suggestions, it would be greatly appreciated. thanks!

 

http://www.youtube.com/user/Davidsfa.../2/PEzdp7MSF2Y


I dont think you should worrie,...think...

 

I watched that video in the link. Aside from his being Canadian, he is very wrong about oil. It does indeed "wear out" despite his assertion to the contrary. Modern engine oils have additives. Some are friction modifiers to increase shear strength and lower wear, but the most important are the ones that help the oil deal with contaminants, water being the primary one. Water is a natural occuring byproduct of combustion and it is usually eliminated from the oil by getting it to operating temperature and keeping it there for a period of time. Unfortunately, we often do a lot of short-hop driving that negates our ability to get up to temperature and keep it there long enough to evaporate the moisture thast occurs. That's where additives come into play and help keep that moisture from turning the oil into sludge. But as time goes by these additives break down and can no longer do their job.
So, oil does indeed wear out regardless of how clean it may look. Oil change intervals should be tailored to the type of oil you use and the kind of driving you do. If most of your driving is in the city and of short distances, then oil should be changed regularly, maybe even earlier than typical. If long drives at freeway speeds are common then you can probably get away with a longer service interval.
As for the original question, while water in the oil is usually an indicator of a leak in the cooling system, it can also be an indicator that your oil needs changing because it can no longer deal with the naturally-occuring moisture from combustion. The best way to find out is to send an oil sample out for analysis. Not only can they tell you if there's coolant in your oil, but they will give you a breakdown of any metals in the oil, which can determine if engine wear is normal or excessive indicating an imminent bearing failure or other issue. I use this company:
http://www.oaitesting.com/

For less than $30 I can keep up with how my engine is wearing and its overall condition. I do this every other oil change and the peace of mind is well worth it.

 

thank you for the educated info guys. i really appreciate it. i shall look into all those. again, thanks!

 

Well, I've always been told that conventional oils wear out, but Synthetic oils just basically get dirty and that is all.

I didn't watch the video, but a little moisture under the cap is fine. It's when you drain your oil and it comes out milky gray or green that you have issues.

 

From what I've read over the years,(more of them that most people on here are old) is that oil itself does not wear out. The additives get used up and when they do that it's time for a change.
Just my nickles worth.