If you have a newer car, you probably don’t have the choice of using conventional oil. My car calls for 0W20 full synthetic with 10000 mile one year changes. It costs me about $28 to change it myself and if I went to a 15000 mile interval and paid $25 for oil analysis I would save no money and void my warranty. Doesn’t make sense to me.
I’m hearing my dear old dad whispering in my ear right now.
"Oil is the life blood of any engine. If you neglect the oil and oil changes you will be replacing the entire engine."
We did a lot of engine rebuilds and at times did ring jobs and main bearings while the motor was still in the cars.
We inspected everything pretty good and always recommended oil and filter changes at 5000 miles.
If there was some study done that proved beyond a doubt that we can go 15’000 miles on oil changes and this study was not just one group involved…and the proof was evident, then I might consider it.
But just because one group is making the claim is just not the proof that would sway me.
I’m one of the worse users. I just bought a new car with a V6 and in the winter , one bank keeps running to keep the heater warm!!!
un til then I’m not budging at changing my oil every 5000 miles.
Yosemite
In order to be convinced that we’d actually save 550 million gallons of oil I’d need to know how many of those extended oil change cars become premature oil burners.
And also if that used oil is no longer available for repurposing, what other than unused oil would replace it? Would we reduce our paving? Would be use other oil byproducts to heat the boilers that currently use repurposed oil? Would we be using new oil for our cars instead of recycled oil?
Sorry. I ain’t buyin’ it. Like so many of these dramatic “statistics”, it’s a very incomplete analysis. It doesn’t talk to the impact of the reduction in the supply of used oil on those applications that used oil serves and on the alternative supplies that would have to be drawn from to serve their needs. Nor does it address the impact of extending oil change intervals on the longevity and/or wear and oil use on the engines involved.
The environmental impact of oil changes is not good, but keep things in perspective.
When you change oil, you use maybe 5 quarts, which should be taken to a recycler.
When you fill your gas tank, you use maybe 75 quarts, and this CO2 is only recycled by Mother Earth.
In 15,000 miles, you will use hundreds of times more fuel than oil, so focus on burning less fuel rather than changing less oil. If you worry your oil changes are harming the environment more than your gasoline use, why not get a bike (and a helmet)?
I like my bicycle and ride it for short trips (I used to ride it miles). but I m not wearing a helmet.
I was a hardcore cyclist, about 80% of it mountain biking, for many years. Having cracked one helmet and dinged a few others, I’d strongly recommend you start wearing one. A busted arm, rib, clav, or leg will heal, but a busted melon could change your life forever.
There was a demonstration we used to show newbies (helmets were mandatory on club rides) where we’d bang a melon on the pavement. The results left an impression on more than the melons.
oh well, I like the wind in my hair. 
the bike I have now is an old gary fisher marlin. its the best I ve ever had except for one ten speed I built myself, which, tho different, was just as good.
the only thing I really did to customize the marlin, was to take off the climbing handles and put hem on the opposite side of the handlebar facing up so I don’t have to bend over as much.
there is a little more wind resistance that way, but its much better as my lower back no longer bends.
this is flat land. but I used to ride a lot. I really enjoyed it. its amazing what you can see on a well tuned quiet bike at night. you can sneak up on cats
oh I had to move the brake lever so ican presss it with my thumb too.
I see one big problem with 15K oil change intervals
Many guys don’t check their oil level at all in between oil changes
Suppose with a 5K interval, the engine is 1 quart down by the time 5K has elapsed
With a 15K interval, the engine might be 3 quarts down
And what if the engine crankcase only holds 4 quarts?
No, no . . . 15K is not a good idea
It might be noted that very, very few automotive journalists are, or ever have been, mechanics and odds are most of them don’t even change their own oil.
Seeing as how car manufacturers often state that a quart of oil per 1000 miles is normal useage and the tendency to buy into that theory by many, that raises the question of how much oil is going to be in that motor after 4k miles has elapsed, much less 10 or 15k. 
@wesw I like the way you think, which parallels my own, it seems. I bicycle as much as possible, which saves wear and tear on the car, and saves money on gasoline as a secondary benefit. I drive less than the 1000 m/yr you mentioned, so change my oil (synthetic) much less often than you also mentioned for your truck.
“I see one big problem with 15K oil change intervals. Many guys don’t check their oil level at all in between oil changes. Suppose with a 5K interval, the engine is 1 quart down by the time 5K has elapsed. With a 15K interval, the engine might be 3 quarts down. And what if the engine crankcase only holds 4 quarts? No, no . . . 15K is not a good idea.”
That is exactly the point that I made in my comment on page 2 of this thread.
I’m glad to see that you agree with me.
“if you doubt that we can effect our environment, try this simple experiment in microcosm. go into your garage, shut the door, start the car. see if you can change the environment in the area.”
During his presidency, Ronald Reagan made a speech in which he came out against tightening anti-pollution regulations as they pertained to vehicles. In a pioneering statement of scientific…fact…Reagan declared that, “trees emit more pollution than cars”.
In response to the POTUS, the president of The Sierra Club offered a unique challenge.
He said, “Mr. Reagan, I will lock myself in a garage with a tree if you will lock yourself in a garage with a car whose engine is running”.
Apparently RR did not take him up on this challenge.
@Caddyman
"…because very few if them weigh 300 lbs."
Exactly. It’s a life style difference. Instead of sitting and eating, others get up and walk, run and dance.
Btw, just passing on the “real” discussion.
lol, darn, i thought i was the the first to use this example.
but this does demonstrate how the money effects common sense in politics. i liked Reagan when first elected when i was in 9th grade, by the time i graduated in 85 i thought he was horrible.
now after seeing all that resulted from his work, i think he did some great things. but there is still things like you posted and the Ollie north thing, that i just don t get.
ben carson is my current favorite one who might run for pres.
@samemountainbike
It has happen !!!
"what I disagree with is trying to go far more miles between oil changes then the manufacturer recommends "
Am I correct in assuming you have now come over to the dark side and are OK with 10k oil changes as recommended by the manufacturer. If so, we have now moved the bar from 2500 to 5k to 10 k in just a few weeks. Tomorrow, sealed systems without dip sticks for the life of the car…well, not mine !
With methane gas now being released in areas we thought had permafrost adding to the woes of the environment, oil use minimizing might be on everyone’s mind.
Btw @wesw Just to show you I respect your avatar.
…and who would that lovely woman be @dagosa?
I think you know mine is my great grandmother mary hopkins
“Mom” she was a wise and funny lady.
I remember a comment by her at 94, a few months before she passed. She said to me; " getting old is terrible. I hurt so much more then when I was younger. I wish I were 90 again. Everything is relative you know. "
My sister in law has a 2008 bmw 535 that she’s had since new and the oil gets changed when the cars computer tells her which is between 15k and 18k. Car has over 120k and doesn’t burn a drop. I do the same with my bmw and the one I had before with no problems. Also, bmw’s have an electronic dipstick and when your down a quart the light comes on and you need to add a quart in 100 miles, but I’ve never had to add any oil.
I’m ok going longer if you use the right oil.
what am I compelled to post for?.. don’t know, but my two cents after reading @Whitey 's synopsis only:
I like the idea of analyzing the oil - don’t know anything about it, but sounds like the way to understand what your engine is saying.
it seems to me that the service interval from the car’s manual is a lower limit - in the event there is great variability in the demands on engine, that lower limit will cover it.
recycling - as in recycling oil here - is a beautiful idea, until you think about - never mind doing - the sums on the energy through the whole process. For oil, I think it is the only option due to laws.
@dagosa I also see this as yet another oil change thread. What can be done, condense them all into a running oil change thread? why does that sound familiar?
BTW I am poking through responses in fragments, didn’t pore over all this.
how do I put carriage returns in here??