My opinion on this topic is different because my view is different. There are three groups who read Cartalk, not just one.
First, those of us who come to find out information on our own cars, and how to care for them, and what to do if bad things happen.
I really don’t care what this group does on oil changes. It’s your car; your money; your business. If you want to change oil every 12 miles, I don’t give a hoot.
However, there are two other groups who use Cartalk.
Second group is the general public, who at times view Cartalk as a good source of accurate and up to date information on cars. If Cartalk forums continues to use the same old theories on oil changes, IF oil life is indeed changing, this forum is going to be a laughingstock.
We have no idea how many people read our postings. It is not uncommon to have 5 or 10 readers for every person who posts. It may be proprietary data, but our moderator probably knows.
I moderate one low traffic board, on certain social issues important to men. We may not get one posting per month, and it will be mine. But, eventually some of our postings accumulate 100 or more views, since one can read without logging in, except the Members Only thread.
I would expect a high traffic board like Cartalk to have even more “lurkers”, as they are called. People who come to research specific information they need, and of course usually referred by Google or another search engine.
We still get reports of oil change places telling their customers to bring their cars back after only 3,000 miles, which is really lame.
And, lame is what this board will be if we are unwilling to supply updated information on oil life, if indeed it is changing.
But, wait, I said two more groups. We do have professional mechanics here. A couple very good ones. If all mechanics were as good as our best ones, mechanics would not generally be viewed by the public as incompetent thieves. Like it or not, alas, that is the general view by the public of mechanics. Which is why this board has Mechanix Files to publicize the best mechanics.
As a pro, if there is a dramatic change in any aspect of car maintenance and service, it behooves you to know it.
Triedaq above said he got a letter from Toyota telling him he could extend Sienna oil changes to 10,000 miles. That is the manufacturer recommendation, not my personal opinion. In spite of sometimes sarcastic remarks by the usual suspects, Toyota is conservative on maintenance recommendations.
That to me is a major indication that something has changed dramatically. My theory which I have stated above is that cleaner burning motors extend oil life. Theories are made to be proven or disproved. I have an older Sienna, and will most likely never buy a newer one, being 75 years old.
There are two ways to find out. If someone knows how to communicate with an oil lab, ask them the question if newer cleaner burning motors can reasonably have extended oil changes. There may be legal or political reasons not to answer correctly, of course.
The other way is for someone, anyone, with a 2017 car, such as Sienna, to wait until their chosen oil life cycle, and when changing oil, send in a sample and then report the results. As I did many years ago, when I learned my Sienna with my driving cycle could go over 10,000 miles with Mobil-1 EP, totally contrary to consensus on this board.
My 2009 Mexican Sienna is not a good sample. It was driven 50.000 miles in our state capitol which produces conditions much like Brooklyn, NYC in the late 60’s when I last drove there. The first oil change dirtied very fast. The second one was much cleaner. If it cleans up, maybe I can use it, but not yet. So, I have no way to obtain data, and the 2009 is 8 years old as well, thus not valid data.
I say again, I don’t care what you do, but that is my viewpoint. But, it would be a public service if this board were able to supply valid information.