Synthetic Oil? Not the BEST choice

[EMYST13]

Actually, for internal combustion engines with pressurized oil circulation and filters synthetic blend is superior to synthetic.

I used to be a "full synthetic in everything" kind of guy. Way back in the day I even used and sold Amsoil. But about a decade ago I bought a piston airplane. Keeping the airplane engine running well is more important in that than my Ford F350 diesel, Lexus IS, Yamaha Super Tenere, John Deere and Kubota tractors, Kubota Zero Turn, generators, air compressors, etc. So when I went looking for a full synthetic piston airplane engine specific oil and could not find one I was curious as to why not?

I found an excellent article written by an Exxon oil engineer that answered the question. While synthetics have superior anti-corrosion, shear strength, resistance to break-down at high temperatures etc. they do have three negatives.

First, they are more expensive.

Second, full synthetic oils do not have the natural solvency of mineral oil.

Third, full synthetic oils do not suspend particles as well as mineral oil.

So in an application where there is no pressurized circulation from a pump and a filter - say in a rear end / differential full synthetic is superior.

But when there is a pump and the oil circulates and eventually passes through a filter a synthetic blend is superior because it can suspend particles (combustion by-products like carbon, wear items like small metal particles, even dirt, etc.) and carry them suspended in the oil until it passes through the filter medium and is caught.

Full synthetic oils do not do as good a job suspending particles so the abrasive particles end up dropping out and gunking up the lower areas where oil is present rather than being filtered.

Mineral oil (non-synthetic base stock) also is a more effective solvent than synthetic.

So given the choice between non-synthetic, synthetic blend, and full synthetic the best choice for engines with a filter is synthetic blend as it combines the benefits from both types of oil.

No manufacture makes a full synthetic piston airplane engine specific oil because the airplane engines are not water cooled so they have more combustion by-products than water-cooled / temperature regulated engines. They also burn fuel with lead so there is lead residue in the combustion blow-by that gets into the oil.

One manufacture did make a full synthetic piston airplane engine oil for a time - Phillips - but they ended up buying some airplane engines after valves stuck because the lead particles were not broken down by the solvency of mineral oil or carried to the filter and filtered out by the particle suspension capability of mineral oil. So the lead particles stayed in the oil and built up on the valve stems and caused valves to stick. So they stopped making the oil.

I use Exxon Elite which is a synthetic blend and I use Rotella Synthetic Blend in my diesel trucks and tractors and other synthetic blends in motorcycle, etc.

Not many people know that when there is a filter present it is better to use synthetic blend so I thought that might be useful information to people here. It is a bit counter-intuitive because we tend to think more is better.

Full synthetic is better than straight mineral oil in any engine that sits because they tend to have more issues with rust on metal surfaces and full synthetic is far superior in corrosion protection than non-synthetic. But synthetic blend is just as effective at protecting against rust as full synthetic.

Synthetic blend is a bit less expensive than full synthetic but you can't use the extended drain intervals to extremes that some people use with full synthetic because the base stock mineral oil has additive packages that wear out with heat and pressure faster than full synthetic oil loses it's lubrication properties.

At any rate, just passing on what I have learned from the airplane experience. If you want a clean engine with minimal wear and no corrosion then synthetic blend is the superior choice over non-synthetic or full synthetic.

In the rear end / differential / transfer case / gearboxes etc. still go full synthetic for the best protection when there is no filter.

 

[HeliMark]

Interesting about the planes, but to stir the pot a little on that, why is the high performance auto engines like a corvette coming directly from the factory with full synthetic? That much difference between the motorcycle water cooled and the auto?

If you look at the RAM engine site (http://www.ramaircraft.com/Maintenance-Tips/Oil-Recommendations.htm) they recommend not using synthetic or blended. Which always made me wonder as the T210 with a RAM engine I flew, still ate the turbo at around 700 hours. Still kinda made TBO though. And the oil was changed every 25 hours.

I am asking out of curiosity.

Mark

P.S. Just to add, the engine the stock T210 has, has a reputation for eating turbo's right around the 700 hour mark. I had one go 900 hours and the mechanics were amazed....

 

[Checkswrecks]

Oh boy - oil thread!



First off, welcome aboard and thanks for an informative first post. This has been split into it's own thread because it's a separate subject from the OP asking when he could go to synthetic from the OEM oil.

Indeed blends are best for this type of engine with an integral transmission. There are two additional points I was waiting for you to bring up and am going to add, just so they are mentioned. I have no doubt that we have some real oil engineering types aboard and this thread will grow.

The first point that I want to add for the collective is that air-cooled airplane engines and water-cooled engines have large fundamental differences in the needed properties for an oil, one of which you touched on. The extremely wide range of operational temps in the air cooled engine require larger clearances between the valve stem and guide. The airplane engine passes more oil down that clearance and since petroleum retains contaminants far better, both the volume and retention of the contaminants means that they are less likely to get baked to the heads and stems of exhaust valves. Helimark - Note that the heads and turbo are nearly opposites in what they subject the oil to and what they really need. A turbo (and turbine engine) optimally runs on full synthetic. The owner of a car or motorcycle would never put up with the maintenance we need to do for modern TSIO airplane engines with head designs which are still hand-me-downs from the 1940s.

Addition #2 is that part of the reason the petroleum retains contaminants so well is because petroleum molecules hold together better. Petroleum has better shear and splash properties. For contaminants, it means that once carbon and other contaminants are attached to a drop of oil, the drop is less likely to let them go. More important to both airplane and motorcycles, higher shear means that the molecules will last longer in the high loads between integral meshing gearboxes and transmissions. (again, as opposed to the turbo or turbine) It's one reason that car engines have gone to such thin viscosities, and why the rear drive uses such a high viscosity.


So with that, a new oil thread is born . . .


::025::

 

[Davesax36]

So how many miles would you run amsoil in a tenere before changing? I had a friend who ran some 16k miles in his vtx with samples sent for testing periodically. He had no issues.

 

[EMYST13]

I have not used Amsoil in many years (except for their grease which is excellent) simply because I learned that a synthetic blend is better for engines with a filter. There are many good blends available. My personal choice even when I ran Amsoil was to still adhere to the recommended change intervals. I have always been of the opinion expressed in the old saying that oil is cheaper than metal. So I have never been an advocate of long drain intervals. Too many contaminants can get in the oil - everything from metal to carbon to acids to water from condensation, etc.

 

[EMYST13]

Interesting about the planes, but to stir the pot a little on that, why is the high performance auto engines like a corvette coming directly from the factory with full synthetic? That much difference between the motorcycle water cooled and the auto?

If you look at the RAM engine site (http://www.ramaircraft.com/Maintenance-Tips/Oil-Recommendations.htm) they recommend not using synthetic or blended. Which always made me wonder as the T210 with a RAM engine I flew, still ate the turbo at around 700 hours. Still kinda made TBO though. And the oil was changed every 25 hours.

I am asking out of curiosity.

Mark

P.S. Just to add, the engine the stock T210 has, has a reputation for eating turbo's right around the 700 hour mark. I had one go 900 hours and the mechanics were amazed....

Good question... As far as using full synthetic I think the motivation is to improve overall MPG for the fleet. The very thin 5W-20 oils improve MPG slightly and I think the manufacturers care more about that than if it is good for the engine over the long term.

About any oil will make it past the 3 to 5 year or mileage limited warranty if oil change intervals are followed. So it is not necessarily in a manufacture's best interest to have vehicles last many miles and years beyond warranty. That would mean people are not buying their vehicles, parts or services.

That said there are some instances where one type of oil is better. Synthetic is better at adhering to bare metal and preventing rust, it flows better, protects better on cold starts, does not break down as quickly, etc. So it is good for applications where there is no filter or in sealed bearings or turbos or other applications where there is high RPM and heat.

But, internal combustion engines that have filters were designed with a filter so the particles manufacturers knew would be in the oil would not prematurely wear bearings, rings, cylinders, etc. So the full synthetics don't carry the particles suspended as well as blends. Blends are almost as good as full synthetics in protection from corrosion or wear. Blends won't last as long due to mineral (petroleum) base stock additives wearing out / changing with heat, pressure and contaminants.

But I would say the manufacturers know most of their engines will last beyond warranty if maintenance is done even if the absolute best oil is not used. I have a hard time seeing how the 5W-20 oils that pour like water are as good as a bit thicker oil.

The main thing is to change it and change the filter regardless of what you use but it makes sense to me that blends are the best overall choice for most situations.

 

[EMYST13]

[This post and response got run together and have been modified to separate the response from my original post.]

Oh boy - oil thread!



First off, welcome aboard and thanks for an informative first post. This has been split into it's own thread because it's a separate subject from the OP asking when he could go to synthetic from the OEM oil.

Indeed blends are best for this type of engine with an integral transmission. There are two additional points I was waiting for you to bring up and am going to add, just so they are mentioned. I have no doubt that we have some real oil engineering types aboard and this thread will grow.

The first point that I want to add for the collective is that air-cooled airplane engines and water-cooled engines have large fundamental differences in the needed properties for an oil, one of which you touched on. The extremely wide range of operational temps in the air cooled engine require larger clearances between the valve stem and guide. The airplane engine passes more oil down that clearance and since petroleum retains contaminants far better, both the volume and retention of the contaminants means that they are less likely to get baked to the heads and stems of exhaust valves. Helimark - Note that the heads and turbo are nearly opposites in what they subject the oil to and what they really need. A turbo (and turbine engine) optimally runs on full synthetic. The owner of a car or motorcycle would never put up with the maintenance we need to do for modern TSIO airplane engines with head designs which are still hand-me-downs from the 1940s.

Addition #2 is that part of the reason the petroleum retains contaminants so well is because petroleum molecules hold together better. Petroleum has better shear and splash properties. For contaminants, it means that once carbon and other contaminants are attached to a drop of oil, the drop is less likely to let them go. More important to both airplane and motorcycles, higher shear means that the molecules will last longer in the high loads between integral meshing gearboxes and transmissions. (again, as opposed to the turbo or turbine) It's one reason that car engines have gone to such thin viscosities, and why the rear drive uses such a high viscosity.


So with that, a new oil thread is born . . .
::025::

Thank you for moving it to a new thread and for the great comments.Absolutely true about the old 1940 and 1950 technology air-cooled engines. Their tolerances are not nearly as close as modern engines. If it were not for the government "helping" us we would be flying around with Yamaha, Honda, Suzuki, Kawasaki, Toyota, Lexus, Nissan, Ford, Chevy, Dodge, Cummins, Kubota engines in our planes instead of Continental or Lycoming. They would have fuel injection, burn less fuel, be more dependable, have more power, less vibration, etc.New engines and / or water-cooled engines that run within a narrower temperature range have much closer tolerances meaning they are far "tighter" resulting in less blow-by so far fewer combustion by-products get into the oil. But, that said there are still all kinds of contaminants that need to be filtered out to provide optimal protection.

The problem of contaminants in the oil is far more pronounced in an airplane (or for that matter an air cooled motorcycle engine) than a water-cooled engine but it still exists.

Another thing that the majority of motorcycles share with airplanes is they are not typically ran every day by most owners. They sit a lot. Sitting is not good on seals or bare metal. So the blend is important to keep corrosion to a minimum and to help protect during the first few seconds when the engine starts after sitting for several days / weeks / months. So motorcycles are similar to airplanes in:

Some are air cooled

Some are oil cooled

Many sit a lot without starting for days / weeks / months out of the year

When they are driven they are often driven hard (airplanes operate at full or near full throttle far more than most cars)

They both have oil filters (some airplanes have screens instead of spin-on filters)

They are typically smaller displacement for the horsepower they are producing so more stress on engines

Motorcycles differ in many are water cooled, the engines are far better engineered, balanced, have tighter tolerances, and they turn a lot higher RPM than piston aircraft engines.

But both benefit from synthetic blends.

Not sure what is best for a turbo-charged engine.

I know in the past when turbos would spin at high RPM without pressurized lubrication when the engine was shut down without idling after running hard enough to get into turbo boost that full synthetic might have been better. I am not sure what impact they would have now.

I run blends in my Ford turbo diesel truck, John Deere and Kubota turbo tractors. I have never owned a turbo-charged airplane although I have flown a Cessna Turbo 210 but it wasn't mine so I did not research oil for turbocharged aircraft engines.

However since nobody makes a full synthetic airplane oil for piston aircraft (whether turbocharged or normally aspirated) I would say the blend is superior to normal petroleum / mineral base stock oils. If nothing else for the corrosion / rust protection and that the film stays on the bare metal longer to protect on cold start. You are supposed to turn the prop a bit before starting if plane has been sitting to coat the internals with oil but the extra protection from synthetic blends is good even if you do that every time.

It would be interesting to hear from some actual oil engineers (I wish I could find the excellent article written by the Exxon engineer but it was years ago) about the specific applications where full synthetic or even petroleum / mineral base stock non-synthetic would be preferable and why.

But in general, if it has a filter, you are better off with the synthetic blend.

 

[EMYST13]

Interesting about the planes, but to stir the pot a little on that, why is the high performance auto engines like a corvette coming directly from the factory with full synthetic? That much difference between the motorcycle water cooled and the auto?

If you look at the RAM engine site (http://www.ramaircraft.com/Maintenance-Tips/Oil-Recommendations.htm) they recommend not using synthetic or blended. Which always made me wonder as the T210 with a RAM engine I flew, still ate the turbo at around 700 hours. Still kinda made TBO though. And the oil was changed every 25 hours.

I am asking out of curiosity.

Mark

P.S. Just to add, the engine the stock T210 has, has a reputation for eating turbo's right around the 700 hour mark. I had one go 900 hours and the mechanics were amazed....

That was really interesting to read their recommendations. I don't really understand them but interesting. I can't see any reason a blend would not be superior. Here is the link to Exxon Elite which is a semi-synthetic blend specific for aircraft engines. http://www.kafco.co.jp/images/mobil/Exxon_Elite_20W-50_PDS.pdf It far surpasses mineral / petroleum / ash-less disbursement oils in several key areas.

Here is a really old press release with photos showing effectiveness of Exxon Elite which has special anti-rust and anti-wear additives.

http://www.avgas.pl/files/Aviation%20Oil%20Elite%20Arrives.pdf

Here is a newer article with better photos of actual rust.

http://www.eliteavoil.co.uk/Acrobat/controlling_rust.pdf

It is obvious the synthetic blends do a better job protecting against rust. They do so in part because they stay on the metal longer. Partly due to additives. But I think the combination of both rust protection and oil staying on the metal longer to provide better cold-start protection is worth the slight reduction in particle suspension.

I suspect the recommendation to not use synthetics by RAM is because they feel the particle suspension is better in AD oils with no synthetic stock blended. They are probably right but if you still get good suspension with blends but have better corrosion protection and the oil film stays on the metal longer I think the positives outweigh the negatives.

A Blackstone oil analysis showed only minimal differences in what they found in oil sent in for analysis but they were not tearing the engine down and looking at how clean it was internally, carbon, rust, etc. - just what metal particles are found in the oil samples. I would expect anyone going to the trouble and expense of having oil sampling for trend analysis done would be doing pretty good maintenance and any of the oils would perform pretty well in terms of preventing major wear - so it does not surprise me the metal particles found in synthetic blends and non-synthetic blends were similar.

But from what I read the main culprit for airplane engines that do not make it to TBO is moisture and rust. So if oils were compared on which engines made it to TBO I think the blends would outperform simply due to their much better protection from rust.

 

[Ramseybella]

Time to be mixing my own blend? :

 

[WJBertrand]

So if a synthetic is less able to suspend contaminants / particulate than a blend, would it follow that there should be more deposits in an engine that been run exclusively on synthetic? Bike engines I've opened that were run on nothing but synthetic were extremely clean inside, even with advanced mileages such as 80,000 - 150,000 miles. The insides looked like new castings that clean oil had been poured on. How much better can that get?

My current ST1300 has 150,000+ miles on it and as part of troubleshooting a misfire, leak down and compression testing was performed. Leak down was 5% and compression was between 200 and 210 PSI. Good enough for a new engine according to the shop that did it. I've run this engine exclusively on MC specific synthetic changed every 5K.

 

[Bryn]

EMYST13,

Thanks for posting....hope you don't mind but I've copied what you have said over to UKGSer.com where I frequent, it makes for intersting reading

I am on 10/40 semi synthetic in my S10 , seems that is a good choice ::003::

 

[Checkswrecks]

So if a synthetic is less able to suspend contaminants / particulate than a blend, would it follow that there should be more deposits in an engine that been run exclusively on synthetic? Bike engines I've opened that were run on nothing but synthetic were extremely clean inside, even with advanced mileages such as 80,000 - 150,000 miles. The insides looked like new castings that clean oil had been poured on. How much better can that get?

My current ST1300 has 150,000+ miles on it and as part of troubleshooting a misfire, leak down and compression testing was performed. Leak down was 5% and compression was between 200 and 210 PSI. Good enough for a new engine according to the shop that did it. I've run this engine exclusively on MC specific synthetic changed every 5K.

No.


The biggest contaminant by far is simple carbon and synthetics generate a lot less of it. Like I said, an air-cooled airplane engine is an invalid comparison with these water-cooled engines which are closer to modern auto design. The good folks at the AFRL fuels and oil lab in the mid 90s did tests to try contingency oils when called-for oils were not available. Over lunches they'd relate stories about how fast ANY petroleum in their applications could build up and damage turbine engines. Bad news if you're in an F16 with just one engine. But their version of synthetic will kill a wet clutch and not last in an engine with an integral transmission.

Every oil is an extreme set of compromises, even within the different sections of a single engine or gearbox. A more direct answer is that the cleansers in the synthetic additive packages are also better targeted to the environment they are in, because they don't have to first address the carbon base of the petroleum base-stock. The best of the additives will actually attack a petroleum base, hence your super-clean engine. And just since synthetics may pick up less foreign material, they still do carry those materials away to the filter quite well.

Oil threads typically become esoteric discussions about how many angels can dance on the head of a pin, and this one is already no different. Change the oil and filter on the recommended schedules and within the recommended stuff as called for by any manufacturer and you'll be fine.

 

[HeliMark]

Thanks Checkswrecks and Emyst13. Still interesting that RAM would not want maybe a semi-blend for the high heat of the turbo.

I have always used synthetic more for the reason of riding in warm temp during the summer. Great explanations here, and on my next oil change, I just may change over to the blended and see how it runs.

Mark

 

[fred-houston]

I use Lucas 10W40 Semi-Synthetic Motorcycle Oil in all my bikes. It is easy to get in my area, price is not too bad, and I don't have to try and remember which oil is in which bike.

As for it being the best oil? I have no idea, Lucas is a major name and has been around for a long time, so I guess their product is about as good as any. I always change oil at 6 months or 4000 miles, and since I never have had an oil related failure, I guess that is good enough.

 

[Pterodactyl]

Of note is that the article was written by an Exxon oil engineer. To be blunt, one is being naive to think that an employee of an petroleum producing firm can be viewed as unbiased or as presenting true, unvarnished scientific fact. I have no idea if the article is fact or fiction, but I doubt the author publishes anything related to petroleum without the consent and editorial approval of Exxon, so I have sufficient reason to be skeptical.

 

[Checkswrecks]

Here are over 200 pages of motorcycle oil threads, so you can get views from all sides.
http://www.bobistheoilguy.com/forums/ubbthreads.php/forums/9/1/Motorcycles_and_Motorcycle_Lub
::003::

 

[JRE]

I've read many an oil thread and there are always arguments for each side which can be very compelling. Similar to the best break in procedure. I have no idea what's BEST to use (especially in aircraft engines) but I do know that for bikes any of the three (dino, blend, synth) will do the job very well providing you do a change at the proper intervals or even more often. Will the BEST one extend the life of the engine/components over the "inferior" ones? Probably but is it enough of a difference to even perceive and how many will keep their bikes long enough to reap the benefits (or detriments) of their oil choice? Probably very few.

I say ::021::

 

[EMYST13]

Of note is that the article was written by an Exxon oil engineer. To be blunt, one is being naive to think that an employee of an petroleum producing firm can be viewed as unbiased or as presenting true, unvarnished scientific fact. I have no idea if the article is fact or fiction, but I doubt the author publishes anything related to petroleum without the consent and editorial approval of Exxon, so I have sufficient reason to be skeptical.

True, but the Exxon engineer was not responding to why Exxon's product was superior to competitors. He was responding to a question of why no oil manufacture produced a full-synthetic oil for piston aircraft engines. His explanation was not why Exxon Elite was the best choice but rather why Exxon Elite was semi-synthetic rather than full-synthetic.

If Exxon wanted to be fully self-serving they could produce a full-synthetic, sell it for more per quart, and claim it is better.

I was not advocating for a particular oil brand. All I am saying is the vast majority of people (myself included before I did the research) assume that full-synthetic is better than synthetic blend or non-synthetic oil - so we buy and use it because we want the best protection possible for our engines, transmissions, rear ends, etc. when that is not necessarily the case.

Engine oil (just like most other products) offers many options. One brand, or one type, is not "the best" for every situation. The various brands and types are engineered for specific purposes. Some are better for diesel because they are engineered with additives to deal with the particular combustion by-products diesel engines produce. While those oils are better for diesel engines they would not be better for gasoline engines. Airplane oil is engineered for the particular needs of airplane engines - namely dealing with lead contamination from 100LL fuel, dealing with condensation from being at high altitude / cold temps and rapidly descending to sea level hot temps and from sitting unused for days or weeks, from the particulars of mid-20th century air cooled engine technology where manufacturing to the tight tolerances of modern automobile engines was not possible, etc - is not necessarily best for any other application. The same goes for motorcycle engines which generally are smaller displacement for the horsepower produced, often air-cooled, have the same issue of sitting unused as airplanes through a good part of the year, and turn very high RPM's.

So a person should use oil engineered for the particular application - airplane oil for airplanes, diesel oil for diesel engines, motorcycle oil for motorcycles, automotive oils for automobiles.

But that said, if the application utilizes an oil pump and filter a full-synthetic is at least not always and probably not ever the best choice. As the engineer explained full synthetic has better lubrication, corrosion protection, flow properties when cold and it lasts longer when compared to non-synthetic or semi-synthetic. However, due to it's molecular structure it cannot suspend contaminant particles as well as either semi-synthetic or non-synthetic. So there is a trade-off.

Using full-synthetic you may have less wear from metal-to-metal contact but what wear particles you do have will not be filtered out as effectively so over the long term (and especially if using extended drain intervals claimed to be a benefit of using full-synthetic oil) you will have more wear due to the particles remaining in the engine rather than being trapped by the filter. If you cut your filters open to inspect you might even believe you have less particles than you do because they simply are not carried to the filter and caught by the filter medium.

Besides wear particles there are combustion by-products that escape past the rings or valves and get into the oil. Especially in high RPM or high compression engines. Carbon can cause wear just like dirt, dust, or metal.

So in general, if it has a filter, full-synthetic won't protect your engine over the long term as well as semi-synthetic unless you are willing to change the oil more frequently to get rid of the particles that are not suspended by the oil and carried to the filter.

Base stock / petroleum / mineral oil is best at particle suspension but must have additive packages blended into the base stock to improve the lubrication properties. Pressure, heat and contamination wear out the additives so the oil begins to revert back to it's natural state and lose it's lubrication, anti-corrosion, and flow properties. That is why for years it was recommended to change oil every 3,000 miles. Over the years additives improved while at the same time engines produced fewer wear and combustion by-products so oil change intervals increased. But it is still prudent to change oil frequently if using non-synthetic.

Between the non-synthetic and full-synthetic oils is the synthetic blend. It isn't as good at lubrication, corrosion protection, extended drain or flow properties as full-synthetic. It isn't as good at particle suspension as non-synthetic. But it is better at suspension than full-synthetic and better at everything else than non-synthetic. So overall, in most cases, it is the best choice for an engine with a filter.

There may be exceptions where some other component matters more than wear - like a turbocharger. But even then most synthetic blends have enough synthetic properties to protect the engine.

Ford Motorcraft 5W-20 is a synthetic blend and it is used in their Ecoboost engines with twin turbochargers. In fact their information on the synthetic blend says it is, "Recommended for use in all vehicles with normally aspirated, turbocharged and supercharged gasoline engines."

I don't know because I don't work for Ford but I suspect they chose a blend for the very reasons I have been saying - it suspends particles better and gets them to the filter. They wanted to drop the viscosity to improve the fuel economy of their fleet - 5W-20 is really thin oil - basically like water. So it already has a tough time suspending particles since it isn't thick at all. Think the difference between water and STP oil additive back in the day. That stuff was like cold maple syrup - really thick and poured slowly. Something that thick will suspend particles. Something thin like water won't nearly as well. So I imagine Ford had competing requirements - lower viscosity to improve economy and suspend particles well enough for the filter to work while still having reasonable drain intervals. That is why they chose a synthetic blend for most applications. Ford does recommend full-synthetic or non-synthetic for some applications. The point being that having a turbo or supercharger does not necessarily mean you can't use a synthetic blend since ecoboost engines with two turbochargers are recommended to run synthetic blend by the manufacture. Ford probably has more turbocharged engines on the road thanks to their ecoboost (each with two) than any other vehicle manufacture.

But as far as the Exxon engineer being biased toward their products - he undoubtedly is - but the article had nothing to do with a particular product but rather a class of products: full-synthetic oil vs non-synthetic or synthetic blend. So I think the information he provided can be trusted.

 

[WJBertrand]

A couple of observations:

1. I thought that the guy being an oil engineer lent credibility to what he said. It is however important to understand his are of expertise. Was he a motor oil engineer or a oil field engineer? It seems like that would make a difference. There are a lot of specialized areas of expertise within oil engineering.

2. Having said that some of this discussion doesn't add up to me. If the synthetic is less adept at suspending particulate then if follows that there should be more debris in the oil pan as mileage accumulates, especially as was pointed out, folks tend to use longer change intervals with synthetic. My experience opening lots of motors tends to contradict that. I usually find engines run on synthetic to be cleaner with respect to sediment/deposits than engine run on conventional oils. I guess I would expect a semi-synthetic to present somewhere between the two extremes.

Related to this,assuming in a synthetic that the particulate must drop out into the sump or settle somewhere in the engine as deposits instead of being picked up by the filter, then the particulate could not be circulated around the engine by the oil pump and therefore not able to cause additional wear. Eventually excess deposits could cause a problem but I've never seen or heard of this with a synthetic.

Additionally, my understanding was that it is the detergent additives that have the most to do with particle suspension and not the base oil stock. Just thinking critically here and can't make the information fit together but perhaps I miss something?

 

[Pterodactyl]

True, but the Exxon engineer was not responding to why Exxon's product was superior to competitors. He was responding to ...............

You may very well be correct. Ultimately we tend to focus on the wrong question in oil threads. Instead of asking, "What is the oil I should use?", we should ask, "What oil should I not use?" Assuming a rider selects an oil that meets the specifications provided by the bike manufacturer, then it would be hard to find a brand of oil (dino, blend or synthetic) that will not perform well.