The antioxidants, detergents, and dispersants tend to darken with exposure to heat. And, suspended extremely tiny particles not large enough to cause abrasion or damage to the engine also contribute to the darkening.
Oh, c'mon, now, you're a better thinker than that! The two notions aren't even remotely comparable. One might as well argue that it's merely "conventional wisdom" that round wheels are better than square.
The filtration characteristics of engine oil filters (including efficacy for particles of various size, measured in microns) aren't printed on the box, but they are not hard to find. There's a great deal of discussion on an ongoing basis over at BITOG, and if you're really interested, you can buy and read the applicable SAE standards for oil filters.
Yes.

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Too many people who were born on third base actually believe they've hit a triple.

Repost, sorry.

Ok.
That's a fair point. It's just that I haven't seen what oil filters actually are catching (or supposedly catching), not that I've gone looking. And one runs across people very often who will defend 3k oil changes as gospel truth (or some other thought)--just because enough people state something is true or important doesn't make it so.

Do some manufacturers recommend changing filters every other change? I can't remember offhand seeing that recommendation, but my memory says I've seen that before. Is that because the motor isn't making "junk" or because the filter isn't catching said junk?
Not familar with BITOG, I'll go look that site up.
<edit>Oh, didn't realize there was a forum there--long time since I saw his websight. I'll go check that out.
Nice return, but I asked for that, didn't I?

Well, yeah, but again, the oil change industry stands to lose a lot of money if people stop repeating the Gospel of Three Thousand...
Quite right, but turn it around and you realise that sometimes everyone says it because it's true. Everyone says your engine has to have a crankshaft or it won't work...and they're probably right.
That was a very common recommendation during the years our slant-6s were made. I haven't checked to see if anybody's still making it, but I can't help considering it a very poor practice. Four quarts of clean oil in the pan + one quart of dirty oil in the filter + one engine startup = five quarts of dirty oil and a used filter that's restrictive to flow, probably not too limber in the antidrainback valve, and probably too limber in the bypass valve. The only justification I can think of for such advice is psychological/marketeering: "Hey, Mr. and Mrs. Potential Customer, you should buy our car because look at the low cost of maintenance!".

One of my first "extreme" experiments with synthetic oil was to put Mobil-1 10w30 in the 2.5 Four in a '92 LeBaron. I changed the filter at 8,000 miles and the oil at 16,000 miles. When the head came off for a gasket change at around 100k miles, the cylinders still had visible cross-hatching, and that engine never developed the piston pin knock most of those engines developed. Anecdotal sample size of one, yeah, but it's one of those things that make y'go "H'mmmm...".
As with most internet forums (except this one, of course! ) there's a considerable amount of noise, but if you're patient enough to sift through it, there's a good deal of knowledge and expertise there.

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Too many people who were born on third base actually believe they've hit a triple.

The question regarding synthetic lubricant was in regard to the topic addressed in the article; that of wear protection of a flat tappet cam. If I have been following this correctly over the years, the tappets must rotate slightly, and if the oil is too slick, this will not happen. So, additives are added to standard oils that produce this rotation. The link to the Skinned Knuckles article, did not mentin this rotation specifically, but stated tht the newer oil designatins, and formulations are OK for flat tappet cams. But synthetics were not specifically mentioned. Maybe they are covered under the certification label as well. I have never paid that much attention, and obviously should start.

One thing I have been told, is that some oil is "real" and some is not petroleum based. I am not sure what the alternative is. It seems that I recall parafin being mentioned. In any event, the only oil I can recall for sure being real any more is Valvoline. A counter guy said Valvoline is who produces Napa's oil. Don't know if he was being truthfull. I always look for Valvoline, and it is not hard to find.

I don't know for sure what any of this means. This kind of thing falls into the catagory of advice that is worth every penny it cost you. Which is nothing. Often times it is just guys standing around B-S-ing, and it is hard to distill the wheat fromt he shaff. I guess with the internet, you can go check for yourself, but there is still the "who do you trust" question on the internet as well. You must remember that most people talk, and listen to prove what they already think is really correct.

Sam

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Yeah, quite true. I just hadn't seen anything recently as to oil filter crud, and realized that I'd been assuming their importance--and just wanted verification. I'll dig around on BITOG for my questions instead, and let this discussion stick with ZDDP.
On the site for my current ride, there's been oil wars and plenty of discussions over UOA's and what's acceptable for an OCI. I just haven't gotten to the point of checking mine--$20 for an analysis just didn't make sense for a $30 oil change. [Now it's over $50, so I might start thinking about doing a few.] Just change the oil if one is worried I thought. Now, there is a debate over changing too soon is actually harmful to the engine, as the additives take time (heat, compression) to fully activate--meaning the worse engine wear is possibly not a cold start but the first few miles after a change (and not just from the initial startup with low pressure as the filter fills, as most of us prefill the filter).

Basically, I guess I'm finding much of what I thought I knew about cars and oil to be half- or mis-truths. Anyhow, maybe your one sample also supports the notion that early OCI's are bad.

Are they arguing about Fram filters yet?
That's certainly an interesting idea. First I've ever heard of it. Does anyone have a credible source for this notion...?
Colour me...skeptical.

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Too many people who were born on third base actually believe they've hit a triple.

Haha--no. Long time belief there that Fram is bottom of the pile.
Have not found a good source yet, so it's all antedotal, I'm afraid--I'm no auto nor oil guy. I have seen posts indicating there is an SAE paper on it, but I have not seen them state that actual paper, nor seen anyone privately do hundreds of UOA's on several motors to see if there is a trend or not. And even if there is a trend (that shorter OCI's cause elevated engine wear), it doesn't automatically mean shorter engine life--wear may be higher but many motors go to the boneyard long before the bores are completely worn out.

I did find this:
http://forums.tdiclub.com/showthread.php?t=136238
Take it as another single datapoint. And for a very modern motor with very modern oils at that. I'll keep looking to see if I can find evidence against shorter OCI or not. I may be completely off base on this, and short OCI's perfectly fine--I'd like to know too.

I'm one of the promulgators of that view of Fram's pathetic excuses for filters...not because I've heard it a zillion times, but because I've scrutinised enough Fram (and other brand) filters to have clearly seen the evidence.

Interesting results that guy with the TDI had concerning initial vs. subsequent engine wear. I've pointed my oils guru at it and will be keen to see what he has to say.

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Too many people who were born on third base actually believe they've hit a triple.

The Oil I use is paraffin based. It has a green color to it, and it is twice as slick as Valvoline or Rotella. (seriously) It does a super job of cleaning your engine, but I believe it's too slick, my rings haven't fully seated yet, and it's been 800 (hard ) miles. I'm looking at Valvoline for my next oil change....

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225 Cubic Inches of Iron-Head American Muscle

225 bored .040 /.100 off block, Schneider Cam 224@.050~ .480 lift - Stock valves, blended bowls, Offenhauser intake with 500 Edelbrock carb

Consider my left eyebrow raised until I see some support for that claim.

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Too many people who were born on third base actually believe they've hit a triple.

...and here's what my oil go-to guy had to say when I pointed him at that thread on tdiclub:

"You could change your oil every 1000 miles and other than being a total waste in so many ways, no harm would be done to the engine...except...most likely these results are due to crud in the new oil. I don't mean to freak you out, but some oils are not exactly particulate-free when virginal, if you know what I mean!" A couple trips through the oil filter and the new-oil particulates are sequestered.

That is a simpler, more logical explanation to me than "the oil additives aren't active until they're exposed to heat and pressure".

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Too many people who were born on third base actually believe they've hit a triple.

OK why would you have WAX based oil?????
Frank

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Scrapple: Because a mind is a terrible thing to waste.
73 Duster - Race Car
66 Dart Wagon - DD
178" FED
82 D150
All Slant powered

"Paraffin" doesn't necessarily mean "wax". In North America we call the white candle wax "paraffin wax", so that's the usage we're familiar with. And in the UK they call "paraffin" what we call "kerosene".

But paraffin is a term that refers to a large group of hydrocarbons. Methane gas is a paraffin. Octane is a paraffin. See here for more info.

As for paraffin-based oil, well...I'm not raising my eyebrow because I think BBB is telling us fibs. I'm raising my eyebrow because for years it was common knowledge that you didn't want to use Pennzoil (or was it Quaker State?), because it contained paraffin, which is wax, which caused sludge. Those brands might've been unfairly targeted by a piece of "common knowledge" that was overly simplified and not well grounded in fact.

Now it looks like some oil company or another (BBB, who makes this magical green oil of yours? I'm guessing it's Schaeffer's — they seem to make a big deal out of their "100% paraffin base" oils) is advertising that paraffin makes their oil twice as slick as non-paraffin oil. Key word: advertising. I also see the "oil's too slick, engine didn't break in" mythology raising its head again. That was a popular but unfounded argument against synthetic engine oil.

So we really need to be specific when we use the word "paraffin". Obviously we don't want the heavier paraffins (wax, etc.) in our engine oil, but without the lighter paraffins (octane, etc.) our cars wouldn't run at all well, and without the even lighter paraffins (methane) eating a big bowl of chili just wouldn't be the same experience.

There is a huge lot of engine oil info here. It's written from a motorcycle perspective, but most of it is largely applicable to automotive engines. There's a fair amount of discussion of paraffins, but this author (like many of us) seems to be using the word "paraffins" when he really means "heavy paraffins".

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Too many people who were born on third base actually believe they've hit a triple.

I don't want to argue with your guy nor you, but one last shot and then I'll shut up. Afterall, it's a pretty small effect I think, if it does exist.

In that thread, the fellow tested his oil initially after 94 miles. Whatever was in the virgin oil, and whatever was left in the sump, after going through the filter a number of times, tested at 2ppm. He then drove 1917 miles, tested, and had a total count of 8ppm. This increase of 6ppm in 1917 miles is 3.12ppm/kmiles. Another 1996 miles driven, the Fe count was then measured at 10 total, or an increase of only 2ppm this time, a lower rate of wear (2ppm/kmile). The last sample was after another 2001 miles, with 15ppm total, or an increase of 5ppm, for 2.5ppm/kmile wear rate.

The second case showed a similar trend: at 228miles, baseline was 2ppm; 1788 miles later, it gained another 5 for 2.79ppm/kmile. 2303 miles later, Fe count did not increase; and the last sample showed a rate of 1.84ppm/kmile.

Now, it's a small trend, small enough it shouldn't matter. Maybe it's a quirk of his motor. Maybe it shows how poor the testing method is (maybe it's +/-5ppm for all I know). Beats me, I'm not an oil guy nor a true motorhead. Just something I came across, and if it can be proven wrong, then so be it.