Determining oil change intervals via analysis

[Elmo P. Shagnasty]

Comparing oil changes to insurance is simply stupid. They aren't equivalent at all. You buy insurance to help when crap happens.

In your world, maybe.

 

[Elmo P. Shagnasty]

The closest I've
seen to a real-world test is the one that CR did many years ago with a taxi fleet. They found no measurable wear in engines changed at 6,000 miles (if memory serves) running plain old dino oil.

And when you run your car like a taxi, 24/7 with the engine on, those tests will be relevant to you.

If you drive your car like a stay at home mom, a couple miles here and there with the engine never getting warm, that would create different results.

Did CR test those kinds of conditions?

You can't extrapolate the CR taxi test into the normal world where cars aren't run like taxis.

 

[Elmo P. Shagnasty]

http://www.tegger.com/hondafaq/sludge/cleaning_sludge.html

I think your cut and paste keys are stuck. This is meaningless and you can't even figure that out.[/QUOTE]

You asked someone to show you something that could break inside the engine due to insufficient oil changes. From that page: "If the owner had left it long enough, the pickup would eventually have choked on the sludge, causing oil starvation and engine seizure."

 

[Mike Marlow]

And why not change oil at 1,000 miles rather than 3,000 as that would reduce wear even more right? How about 500 miles? Why not change it every morning before going to work?

What!? You mean your wife does not do this for you now Matt? Man, we gotta talk...

 

[Mike Marlow]

And when you run your car like a taxi, 24/7 with the engine on, those tests will be relevant to you.

If you drive your car like a stay at home mom, a couple miles here and there with the engine never getting warm, that would create different results.

Did CR test those kinds of conditions?

You can't extrapolate the CR taxi test into the normal world where cars aren't run like taxis.

Well, between the sludge link posts and this reply, you've pretty much proven yourself to be completely in the dark. Here - just for the sake of accuracy, I've pasted in that part of Matt's original response to me which states exactly what you babble about above. You know the part - it's the part you snipped to make your post.

Matt said...

"Now, there were several shortcomings in their test, in my opinion, such as taxis don't really represent how most people drive as they rarely get thermally cycled and there is reason to believe that cold starts are one of the highest wear activities an engine sees. And, again if memory serves, they ran the engines for only 60,000 miles. This is hardly a stress test for a modern engine.

However, imperfect as it was, this is about the only test I've seen that was even close to scientifically conducted."

It pays to read what is posted and to give yourself that extra minute to think about it before snipping relevant parts and running off on tangents with misrepresentations of what was said.

 

[Tegger]

"Nasty" wrote in

"TeGGeR" wrote:

>
>
> Post this to rec.autos.tech. Best place for answers.
>
> Make sure your subject there is ON topic!

Guess that means you DO mind me tossing it out here. Sorry. But thanks for the tip.

No, that's not what I meant. I meant you will find many more GM experts there than here.

The OT thing was meant to be a joke. It evidently fell flat.

 

[Guest]

You would be surprised how easy it is to learn what the data means.

That said, it isn't worth it. It's cheaper just to change the oil.

No, Bob. It isnt easly to learn what it means. It is easy to learn the basics of what it MIGHT mean. I am quite aware of what the chemical analyses MIGHT mean.

It isnt even easy sometimes to get the same numbers from several different oil analysis labs. $20-30 is measly when it comes to doing competent chemical analysis, even with modern equipment. Some of the labs give more reproducible data than others.

But for me, you are right...it isn't worth the time and cost.

 

[Guest]

That all by itself does not

discredit what you do or what you support - it only says it doesn't offer enough for me. It may also be that if this discussion actually reached a level where some sort of empirical evidence was put forth, it might be obvious that the incremental value of more frequent changes, oil analysis, etc. simply do not offer a statistically significant benefit.

This is the way I feel about oil analyses.
There is a real shortage of hard data about how well synthetics and refined petroleum lubricants actually perform.

Flash points, and viscosity, and all the other bits of physical and chemical data mean little or nothing. I want statistical data, which -below the bottom line - will tell what it costs to deliver certain levels of protection and performance.

And you wont get this with cheapass chemical analyses, or even oil company product hype.

 

[Tegger]

"TeGGeR" wrote in

"Nasty" wrote in

>
> "TeGGeR" wrote:
>

>>
>>
>> Post this to rec.autos.tech. Best place for answers.
>>
>> Make sure your subject there is ON topic!
...

The problem is, there are too many potential gotcha's trying to guess what's wrong with a make other than what we specialize in. Not too many non-Honda people are familiar with our Main Relay, for instance.

 

[Matt Whiting]

Because the benefits go on a curve.

That's right. And with good oil, the difference isn't measurable until way beyond 3,000 miles. And with synthetic oil, it is probably way beyond 5,000 miles. So, show us the curve. Show us the data.

Matt

 

[Matt Whiting]

In your world, maybe.

In the real world. You compared oil changes to homeowner's insurance.
Now tell us how they compare.

Actually, your analogy argues against your position. Homeowner's insrurance doesn't protect my home from damage. That suggests that, based on your own analogy, oil changes don't protect your engeing from damage.

Got any other arguments or analogies?

Matt

 

[Michael Pardee]

Are you really going to overhaul a car engine if you see a little extra metal? Most folks will just drive it until it quits anyway as the labor cost is more than the parts in many cars and the consequences of failure are relatively minor. Airplanes are a different matter completely, but few people do preventive overhauls on car engines, even with better information. I'd personally just run a car engine until it showed serious signs of failure even if I had oil analysis evidence that wear was unusually high.

Matt

I agree - the question is "what will you do with the information?" My #2 son had a worn-out Toyota that was giving him intermittent oil pressure warnings. We considered the situation and decided there was nothing we would do differently if the oil pressure was failing or if the sensor was failing; the car wasn't worth the effort to repair any oil problem. It threw a rod a couple months later, but he had no regrets. A little extreme, but the principle applies. Don't ask a question if the answer doesn't help you.

Mike

 

[Matt Whiting]

And when you run your car like a taxi, 24/7 with the engine on, those tests will be relevant to you.

If you drive your car like a stay at home mom, a couple miles here and there with the engine never getting warm, that would create different results.

Did CR test those kinds of conditions?

You can't extrapolate the CR taxi test into the normal world where cars aren't run like taxis.

Which is exactly what I said. Did you read past the first two sentences? I said this test was flawed, but it is the best test I've seen and at least had some semblance of scientific rigor. You've posted nothing even close.

Matt

 

[Matt Whiting]

I think your cut and paste keys are stuck. This is meaningless and you can't even figure that out.

You asked someone to show you something that could break inside the engine due to insufficient oil changes. From that page: "If the owner had left it long enough, the pickup would eventually have choked on the sludge, causing oil starvation and engine seizure."[/QUOTE]

That is complete conjecture. And that post has enough questionable things about it to make it meaningless.

Matt

 

[Matt Whiting]

What!? You mean your wife does not do this for you now Matt? Man, we gotta talk...

Yes, the hardship is great.

Matt

 

[Matt Whiting]

Well, between the sludge link posts and this reply, you've pretty much proven yourself to be completely in the dark. Here - just for the sake of accuracy, I've pasted in that part of Matt's original response to me which states exactly what you babble about above. You know the part - it's the part you snipped to make your post.

Matt said...

"Now, there were several shortcomings in their test, in my opinion, such as taxis don't really represent how most people drive as they rarely get thermally cycled and there is reason to believe that cold starts are one of the highest wear activities an engine sees. And, again if memory serves, they ran the engines for only 60,000 miles. This is hardly a stress test for a modern engine.

However, imperfect as it was, this is about the only test I've seen that was even close to scientifically conducted."

It pays to read what is posted and to give yourself that extra minute to think about it before snipping relevant parts and running off on tangents with misrepresentations of what was said.

Only if you have integrity. If you don't have integrity, you do what he did. Clip the part you like and omit the rest.

I'd really love to see some real data on oil and engine wear and life. I certainly have my opinions, and I've seen testing that shows differences in oils, and I believe those differences have an affect on service life, but I've never found any data to support my opinions or anyone elses.

Matt

 

[Matt Whiting]

No, Bob. It isnt easly to learn what it means. It is easy to learn the basics of what it MIGHT mean. I am quite aware of what the chemical analyses MIGHT mean.

It isnt even easy sometimes to get the same numbers from several different oil analysis labs. $20-30 is measly when it comes to doing competent chemical analysis, even with modern equipment. Some of the labs give more reproducible data than others.

You can skew the results heavily just through the sampling procedure. Take your sample of the first oil to leave the drain and then sample again when it is barely dripping at the end. That can change the results dramatically. Most analysis labs have pretty specific sample taking instructions, but few people are able to follow them precisely and they can make a big difference.

Matt

 

[Gerry]

[original post is likely clipped to save bandwidth]

This should be interesting. I can't wait to see his reply... ;-)

http://www.tegger.com/hondafaq/sludge/cleaning_sludge.html[/QUOTE]

Any engine that bad in 8700 miles has something seriously wrong other than oil change intervals.

gerry

 

[Gerry]

[original post is likely clipped to save bandwidth]

They may, but I've seen no documented proof as to when this is meaningful. Post some of your fleet testing results. If my engine will last 200K with 10,000 miles intervals and the body rusts off at 200K, what is the point of reducing engine wear?

And why not change oil at 1,000 miles rather than 3,000 as that would reduce wear even more right? How about 500 miles? Why not change it every morning before going to work?

Matt

Heck, at this rate, redirect the oil flow so it is never re circulated Add a 100 gallon fresh oil tank and 100 gal holding tank. Ship the "used oil" off to be fully reclaimed to original purity.

That seems the direction the ultra frequent changers really recommend

gerry

 

[Elmo P. Shagnasty]

Heck, at this rate, redirect the oil flow so it is never re circulated Add a 100 gallon fresh oil tank and 100 gal holding tank. Ship the "used oil" off to be fully reclaimed to original purity.

That seems the direction the ultra frequent changers really recommend

And if it cost, oh, $20 for every 3000 miles to do that, why wouldn't you?

Oh--I see. In your world, there's no room for cost/benefit analysis.