Wes, your suggestion is an excellent one. I wholeheartedly agree.
Carolyn?
While it was not clear that they used synthetic oils when not required, it seems safe to assume that they did use them.http://www.calrecycle.ca.gov/Publications/Documents/UsedOil\2008020.pdf
“Synthetics show promise for extended change intervals, but they were not part of this study.”
@ Yosemite,nope wasnt even referring to cars,caterpillar construction equipment mainly-but it can tell you things like how close to desruction the bottom end of your motor is or if you have a leaky headgasket or a hole in your aircleaner system-so maybe its not such a bad deal on a used car you wish to purchase,it can diagnose a lot of ills-Kevin
Thanks for the info Kevin. For some reason I was thinking “Heavy Equiptment”. Must have been a slight hint in that post.
Still, maybe someone out there could answer the other questions if these tests are available out there, for us small repair places or private owners.
Where would we find these testing labs, to send a sample to?
What would be the approx. cost for the testing?
I never thought of a pre-purchase test,…might not be a bad idea.
I’d still be conservative about the results. If they told me I could go to 15’000 miles on oil changes, I’d still change it out at 10’000, to be safe.
Old habits die hard!!!
At least I’d be cutting my consumption in half.
Yosemite
I am so glad this conversation includes a discussion of the science behind oil changes and used oil analysis. Some of you have attempted to make this discussion about politics instead of science, and I think that’s both sad and desperate.
@Whitey Yes, there is some politics involved, but over time, oil change intervals have increased because of better oils and better made engines. However, environmental drivers to reduce waste oil, and manufacturers outdoing themselves by stretching the oil change intervals at the expense of engine life are getting us into unsafely long drain intervals.
The carmakers cover themselves by saying those long intervals are only good under “normal” driving condition, which most drivers never experience. Most driving can be classified as “severe”.
Toyota went out on a limb years ago with their 8000 mile interva and ended up with a lot of sludged up engines. My 2007 Toyota states 5000 miles regardless of driving condition.
The new Toyota 10,000 mile interval needs top quality oils and has some fine print attached to it.
Like many posters here, I play it safe and will stick to 5000 miles with my 2 vehicles.
All the science that I’ve seen says the 15k mile oil changes work for up to 150k miles…Well that’s great for people who only keep their cars for 150k miles. There hasn’t been one shred of evidence that it’s fine for 300k+ miles. I know the 5k oil change works for 300k+ miles.
As for oil analysis…I see it as a total waste. You’ll spend more money having the analysis done then just doing an oil change.
Good morning, sirs. Thanks for your thoughts, and for bringing it back to cars.
Wes and TSM, I think it’s an excellent and timely topic to discuss alternative energy sources. For simplicity’s sake, I think it best to keep our current classification system for topics, without adding in one specifically for energy sources. Sometimes I think I’ll see tumbleweeds blow through when I open up Distracted Driving; it’s pretty sparse for new material. However, its creation predated my assumption of full moderator duties, so I think it’s not going anywhere.
So, please do discuss alternative energy sources, but try to keep it close to their applications in cars. Sure, there are analogues and counterexamples that don’t work in cars, and that’s game…but overall, the rules aren’t going to change. If it starts to drift into politics or something else, I’ll still poke my head in.
As you were!
Carolyn
There’s the school of thought that cars should be equipped with an elapsed time display (easy with modern cars’ digital displays), then change oil based on run time.
There’s much less variation with driving conditions.
For example a 150 hour oil change interval would be 9000 miles for a mostly highway driver who averages 60mph and 3750 miles for a city dweller who averages 25mph.
@MikeInNH: “As for oil analysis…I see it as a total waste. You’ll spend more money having the analysis done then just doing an oil change.”
In some circumstances, that can be a penny wise, pound foolish policy. If you just bought a used car with 50,000 miles on it, and you plan to keep it until it has 200,000 miles, spending $50 on a couple oil analyses might save you significant money over the life of the car.
Imagine the savings you’d get if you manage a fleet of vehicles.
As for oil analysis…I see it as a total waste. You’ll spend more money having the analysis done then just doing an oil change.
I think the idea is to do the analysis a few times at first to figure out a change interval based on your specific vehicle and usage profile. Then you establish a change interval that suits those conditions best with perhaps an AQL check every so often or if a change in conditions warrants. You don’t just keep doing them at every change unless you’re fanatical at uncovering potential engine problems early…
If you just bought a used car with 50,000 miles on it, and you plan to keep it until it has 200,000 miles, spending $50 on a couple oil analyses might save you significant money over the life of the car.
I don’t buy that. You’re assuming that when you have analysis done at 50k miles it’ll be the same results at 100k miles…and then again at 150k miles. I contend it won’t be. Oil analysis will give you different readings over time as the engine ages. So in order to get an accurate reading you’ll have to have periodic oil analysis…which is costly.
@minh,exactly,I think it was amsoil that did oil anylisis,just to prove how good the oil was.on a older engine,if you found a bunch of copper or bearing material,you would have to assume the engine needed a bottom end overhaul before long-on the other hand if a 150K engine tested good on the bottom end,you could reasonably expect to get another 100K out of the engine,by that time the vehicle has probaly turned into a beater or met with some misfortune-Kevin
P.S, So the low buck good looking car may be a bargain after all.
@babbittd, thanks for pointing out that it was mineral oil and not synthetic oil in the California study. I am surprised that it wasn’t because I thought that higher quantities of ZDDP were only available in synthetics. In any case, oil analysis does seem to have a. Real and meaningful use, especially for fleets. For individuals that are comfortable with additional risk, it could be useful. If enough people did it and it showed that they could extend their change intervals, extended oil change intervals could forestall the use of a huge amount of oil for whatever reason you think is worthwhile. It could be environmental, it could be national security, or something else.
And @MikeinNH, you are exactly the person that should not do oil testing. It would cause too much angst. We all have more than enough annoyances each day, and don’t need to add any more. Others can do the big experiment and see how it goes. After the warranty expires, of course.
“Imagine the savings you’d get if you manage a fleet of vehicles.”
For the average driver/DIY’er, an oil change analysis makes no sense. Just change the oil according to schedule. Oil changes are cheap, anyone who thinks they can save money by stretching oil change intervals needs a math lesson. True, there are a few here that keep cars to 300,000 miles but that’s certainly not the norm for the average driver.
Now fleet service, with a large number of identical vehicles under similar use, oil analysis is a necessity to determine the best maintenance matrix. There’s a local courier/delivery service that has does in-house maintenance. The guy there has used oil analysis and determined that for his fleet of Chevy Express vans an oil change interval of 10,000 miles makes sense. He is able to run his rigs to 400,000 miles without any oil-related engine problems. For his Sprinters he changes oil every 15,000 miles.
For a guy with 30+ vehicles, stretching the interval without any engine damage is substantial. For the guy with 2 cars, meh.
@jtsanders Do you think the line I quoted rules out blends?
The authors state in more than one place that they did not use synthetic oil. I think they understand that blends contain synthetic components and would have said they used a blend for that reason.
We all have more than enough annoyances each day, and don't need to add any more. Others can do the big experiment and see how it goes. After the warranty expires, of course
There’d have to be MANY MANY people doing the experiment. Not just a couple.
For the average driver/DIY’er, an oil change analysis makes no sense.
So, who decides that? I found my oil analysis very helpful and informative, and it put to rest the claim here that synthetics give no benefit on ordinary cars.
Oil analysis does far more than check the oil condition. It also tells you a great deal about what is happening inside your motor. Bearing wear and much more. I heartily disagree with the claim that oil analysis makes no sense. and am guessing the commenter has never had an oil analysis done. Anyone who has done one and understood the report would know better.
@irlandes , my comment about it not making sense to the average driver was in the context of the tone of the discussion, which had turned to potential savings by increasing the oil change interval. For the average guy, my comment rings true. Spending the $40 or so for an oil analysis in the hopes of being able to save $35/year on oil changes just doesn’t make sense to me.
Now having an oil analysis done to determine possible engine wear, coolant intrusion, quality of oil, etc. is indeed a valuable tool for anyone planning to keep a vehicle for an extended time OR managing a fleet of vehicles. Your comment about having the analysis done and understanding the report is right on. You’ve got to want the information and you’ve got to understand it.
However it’s my belief that many people would do an analysis just to get validation on the perceived savings of skipping one oil change per year.