E46Fanatics - View Single Post - Interesting info regarding oil drain interval
View Single Post
Old 06-03-2009, 11:57 PM   #38
Registered User
Join Date: Nov 2005
Location: San Jose, CA & Dallas, TX
Posts: 20,209
My Ride: 330cic & R6
Send a message via AIM to TKC
Originally Posted by jeffro3000 View Post
Yea you're right. No one knows more than you.
Re-read my post. No where in there did I say I knew it all...or anything for that matter. I simply stated that I've always changed my oil at 5k and in all my years and many cars, not to mention the 4 I have right now, 2 of which are over 100k miles and 1 at over 200k miles and all run like a champ, I see no need to change my habits due to your article.

And if you'd get off the articles' nuts, I can quote parts of it just like you, it's just that you choose to focus on certain sentences that lead you to say,
"Those of you who change oil every 3-5k to be on the "safe side" are being counterproductive" when NO WHERE in that article does it say that.

Here are the counter highlights:

Engine oils are subjected to a series of industry standard engine dynamometer tests to measure their wear protection capability, sludge and varnish formation tendencies, and fuel efficiency among several other performance attributes before they are approved for use in customer engines. However, these performance attributes are measured at the end of tests and therefore, do not provide any information on how the properties have changed during the tests. In one of our previous studies it was observed that engine oil samples collected from fleet vehicles after 12,000 mile drain interval showed 10-15% lower friction and more importantly, an order of magnitude lower wear rate than those of fresh oils. (FRESH OILS, NOT every 3-5k AS YOU PUT IT) It was also observed that the composition of the tribochemical films formed was quite different on the surface tested with the drain oils from those formed with fresh oils. The objective of this investigation is to demonstrate how the friction and wear performance changed with oil drain intervals. A fleet of three vehicles was run in Las Vegas and oil samples were collected at various drain intervals from 3,000 miles to 15,000 miles. As in the previous study, the results showed that the aged engine oils provide lower friction and much improved wear protection capability. These improvements were observed as early as the 3,000 mile drain interval and continued to the 15,000 mile drain interval.(I like how you skipped just this sentence in your bolding....these improvements were observed as early as the 3k mile to 15k miles....which CLEARLY 3-5k falls between, which you claim "Those of you who change oil every 3-5k to be on the "safe side" are being counterproductive.") The composition of tribochemical films formed on the surface with the 3,000 mile drain interval is similar to that formed with the 12,000 mile drain interval as seen before. These findings could be an enabler for achieving longer drain interval although several other factors must to be considered.Exactly.
Meh, no need to debate this further with you. Like I said originally, my cars run great.
EUROPROJEKTZ - Director, NorCal Chapter
TKC is offline   Reply With Quote