An interesting read from a while back.

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I'm surprised it didn't kick up the storm it usually does. That document would have been great if they had listed the average fuel economy for the fleet. That would have indexed the 6k mile intervals with a little more validity. If they were getting 10mpg, then 6k wasn't a typical 6k or even 9k (maybe).
 
Yeah I was surprised too. I was surprised a bit wiht the results as well.

hmm, I'll have to try harder next time.
 
If you want to
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..you need to also include some inflammatory text with it ...like "See synthetic oil is a waste of money!!" ...and/or "dino is the best ...QED the best!"


Then you watch the fur fly
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That test is a few years old. Current specs at the time were GF-1 and SH. Pennzoil Performax has not been around for a while either.

I'm sure that oils have improved even more since then. I would expect about the same results if that was repeated today.
 
I'd expect even better results if done today. The only thing wrong with the test is that it unfairly assigns "grueling" status to taxi cab usage. The severe duty assigned to commercial deliver/taxi service isn't really due to anything "severe" ..it's due to the inability of mileage to effectively be used as a sensible criterion for oil fatigue.

Do the same test with a fleet equipped with OLM and run synthetic oils side by side with dino's and changed according to the OLM's ..THEN see if there was any effective difference in terms of measured wear ...then you will make a point ..but even that isn't truly anything to base consumer usage on.

Taxi service uses a lot of fuel over a short mileage ..and experiences very few warm up events per mile (or many miles per warm up event - same thing). One factor (fuel enrichment and the byproducts and reactive insults that it includes - and stuff like moisture content) are virtually eliminated from the oil fatigue equation.
 
This CR article was discussed here a few times, quite a few years ago.
I subscribed to CR at that time (1996) and that article made me relax my oil changes routines to 6000 miles (Nissan and Mazda recommended on regular service) on cheapest dino oil. Then, I discovered BITOG in 2002 and the rest is history.

I would venture to say (and I said that already here but I will repeat) that this study contributed greatly to the Toyota sludge problem. CR catered to Toyota owners. These owners learned from CR that short oil changes have no merit anymore. Then every soccer mom driving a few miles each way in hot summers (remember my heat soak post?) squeezed the 7500 miles (allowed and recommended by toyota) from the cheapest dino oil money could buy (by quick lube places, possibly non-detergent variety). The rest is history.
 
I personally feel the test was poorly done and not up to consumer reports usual standards. For example, they told you what the average wear was but not which one was the lowest or which one was the highest. The truth is a .001 difference in bearing clearance over a mere 60,000 miles is huge. But they didn't tell us the actual wear numbers of the vehicles.
The second problem was that it was only 10 months long. You could almost run an engine that long with 3 in one oil (LOL).
Just to stir the pot some more, i will include a link to a Mobil-1 test where they ran an engine for 1,000,000 miles and the engine was still in perfect condition.



http://www.mr2.com/ARTICLE/Mobil1.html
 
That article is actually not entirely accurate. There are more complete accounts of the test that can be found easily with a google search, but the following statement from the above link:

Quote:
AT THE END of the road, when the engine was taken apart, Mobil's engineers discovered that the wear measurements were the same as the manufacturer's specifications.

is not correct. Some internal components, including one main bearig or rod bearing IIRC, was at the point at which it required replacement, as were a few other items, and components did show normal wear.

Also those miles were run almost continuously with few if any real cold starts or particularly stressful conditions.

However I'm hoping the results hold true since I have the same car, now at 313k miles, and I hope that it still has lots of life left. Mostly conventional in mine, BTW.

Back to the Consumer Reports test - when I first read that I was a confirmed synthetic user and went to some lengths to pick the article apart to justify my choice - I considered many of the things already mentioned here and remained satisfied that I was right in my choice of oil and that CU had missed some important details.

Later, after finding BITOG and learning quite a bit more about the differences between synthetics and conventional oil, and particularly about the effects on wear rates of running one versus the other, it all fell into place. Synthetic has advantages, but they are mostly confined to long drains and unusual operating parameters. The wear advantage, that everybody has long since assumed they have, just doesn't seem to exist.

Since then I have run conventional only in all my vehicles, even the high mileage ones that I want to last forever - until my recent experimentation with Redline, that is.
 
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The most important thing in engine life all, filters ,care and operation is the numbers of warm up cycles if you have a car that does all long freeway miles the engine will last longer than if the daily commute is 2 miles in the A,M, then 2 miles home in the P.M.
 
I too believe synthetic oil has advantages, but I believe it is more than just limited to extended drains and extreme conditions. We can mention sludge formation and cleanliness also important for long life. We can also debate how it can reduce wear by virtue of its better lubricity. But this is just my humble opinion.
I read the cu article when it was originally printed, late 80's I believe and even then I knew 60,000 miles is almost meaningless. But even with that low mileage they found difference in wear patterns which they said were unimportant. They chose to give us an overall average which is useless.
Synthetic basestocks due offer advantages in extreme heat and cold as well as lubricity. Especially polyol ester. You mentioned using redline oil so I am attaching a link about ester basestocks. You can scroll down to the polyol ester section. I found it very interesting.



http://www.diolube.com/ESTERS IN SYNTHETIC LUBRICANTS.htm
 
I often wish CU would provide more raw data in all their testing. However, 60k miles is far from meaningless when the actual quantity of wear is systematically measured during teardown. Also, we will never know for sure, but my reading of the report is that the differences they found between oils did not fall into any pattern - i.e., synthetic did not have any tendency to produce even slightly better numbers - and consequently the conclusion of the differences not being significant is probably completely correct. If so, the 60k mile wear rate would logically extrapolate itself throughout the remainder of the engine's life.

My interest in Redline is thanks to its POE base. You may be aware of the importance of polarity in engine oil. Conventional oils are polar thanks to the unsaturated nature of their carbon chains. As they are further refined those chains saturate, making the molecules both more stable and less polar. PAOs are in fact completely saturated and not at all polar. Polarity gives the oil its ability to stick to metal surfaces and is therefore critical to film strength, and for that reason PAOs need to be mixed with other base stocks - traditionally esters, now often lower-group oils - to perform properly.

POEs do not have that disadvantage and those used in motor oils are heavily polar. That can lead to odd apparent wear patterns as they react with the engine's metal surfaces, but it also gives them excellent film strength, as evidenced by higher HTHS than other oils of equivalent viscosity.

PEOs notwithstanding, I have not seen any evidence at all - and I have looked - that synthetic oil will make an engine wear less quickly than conventionals, and in fact it often seems as though the best UOA results tend to come from plain old conventional oils. There is an excellent example of that posted very recently in which poster Artemedes ran a fill of Pennzoil YB after two consecutive PP runs and wear went down quite dramatically:

http://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=1220292&gonew=1#UNREAD

As for cleanliness I believe that is only an issue if an engine has design flaws or if an appropriate OCI is not followed. Synthetics do of course allow for longer intervals - however, when changed at appropriate intervals, conventionals appear quite able to keep an engine perfectly clean.

Thanks for the link, by the way. Interesting indeed.
 
If I read your post correctly, you seem to imply that cars will last longer with dino oil than with synthetic oil. I have a hard time believing that is true.

First of all, the example you used, poster Artemedes, compared 5w-20 synthetic to 5w-30 Dino oil. Second, the car only had 15,000 miles with the PP and in all likely hood still had some break in metals floating around.

IMHO UOA are not really designed to compare motor oils. They give a snapshot of your oil and can tell you if something is drastically wrong. IE: fuel dilution, head gasket leak etc. Larger particles are stopped in the filter and never measured at all. So it can not give a true picture of how much wear is actually occuring. That is why engine tear downs are done when looking for solid information. CU is a perfect example of this procedure.

Besides , truth be told there could be a million different reasons for the higher wear numbers. Sludge breaking up, or even FE in the original virgin oil. Mobil1 and RL are both known for that. When you look at long term UOA'S you will see that sometimes there are spikes in wear numbers even when using the same oil, this makes comparing oils even more difficult.

I believe that ester based oils will drastically reduce wear in an engine. Smokey Yunick was one of the first engine builders/ racers to switch to synthetic. He used a pure ester based oil not available for street use. He flat out stated that his engines would not break-in with this oil. He was forced to break-in the engine with dino oil , then switch over to the synthetic. He also had problems with some of his rally cars blowing bottom ends from oil starvation caused by high g force turns over 1.25 g's. When he switched to the synthetic oil not only did he stop losing engines, but there was no discernable damage or wear to the bearings.

I am interested in the Redline for the same reason as you. The POE basestock. That said, I do not believe you will the same big benefits with reagrds to wear with PAO oils. They do however, still offer benefits with regards to heat, cold, cleanliness, and longer oil drains
 
Originally Posted By: glennc
the 60k mile wear rate would logically extrapolate itself throughout the remainder of the engine's life.



The only thing I would like to point out is the first 60k will show the break in wear, the next 60k should carry out the same wear pattern minus the break in wear. You would have to run these tests to 180k to confirm this.

However, the test is what it is. Your engine will run for a long time and getting rid of a car at 100k is probably not a good decision if it is made based on mileage alone.
 
Originally Posted By: pev223
...I am attaching a link about ester basestocks. You can scroll down to the polyol ester section. I found it very interesting.

http://www.diolube.com/ESTERS IN SYNTHETIC LUBRICANTS.htm


Just for the record, the Diolube people lifted that write-up on esters from their competitor's website, Hatco, without permission. Real high integrity!

I wrote that article while working at Hatco and it was on their website for many years - the current version on the Hatco site has been modified as I retired last year.

Tom NJ
 
Well now that I am retired, I'm far too busy to be writing papers
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But BITOG is on my forum list and I chime in from time to time.

TomNJ
 
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