Member "Dnewton3"....I got a oil question?

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Originally Posted By: JXW
Ponch I have been using syn oils for over 20 years now. I have had conventional oil put in both my bike and cars over the years when I expected to get syn oils. On my bike I had some type of bulk HD oil put in it and I could tell within 5 miles something was wrong. The bike ran hot, was losing power and exhibited overall poor operating charateristics. This is a machine with a basic two cylinder air cooled engine, okay? I also had a same experience with a car that was filled with castrol GTX not the Castrol Syntec that I was using. Within 5 miles I called my wife and questioned her on the oil used to find that conventional was used by mistake.

Some people might eat 10 donuts a day or smoke two packs a day and live for 70 years--that doesn't mean they are healthy right? Same argument from me on conventional vs. syn. You can get by on conventional but syn is better all the way around. I know this from my real world experience, mileages driven and different applications (bikes, cars, trucks and tractors).

Conventional oils are better than ever but syn still leads them all hands down.


Forgive me for being rude, but that would be the mythology and rhetoric I speak of. I mean no personal afront, but I call into question your basis of "testimony". And your "seat-of-the-pants-o-meter" is calibrated how?

Countless thousands of used oil analysis show no statistically significant advantage to syn's in short-to-moderate OCI durations. Doug's data, gleaned from hundred's of thousands of miles, shows that syns can outperform in longer distances. And, as Jim mentioned, filtration plays a HUGE part of it.

The REAL valid use of used oil analysis is to monitor your oil health (which is a direct indication) and the equipment health (an indirect indication). Using safe, practical predetermined condemnation levels for wear metals, insolubles, vis, contaminants (soot, fuel, coolant, silicon/dirt, etc) will help determine when to change any oil.

I take exception to your comments. Not to taunt you, but to challenge you in a gentlemanly way. This is not about what argument might take place, but rather what good-natured debate might bring forth. Perhaps you are correct; perhaps your vehicles did miracuously perform "better" in five minutes of run time with syn's. But I find that hard to believe, and nearly impossible for you to quantify.

I'll be the first to admit I suffer from diarhea of the keyboard; many people think I ramble on, and perhaps I do. But I typically try to tie in my theory with hard data and evidence. There are so many used oil analysis here to prove my point. Doug's data is clearly showing us he knows how to operate a fleet with the right application of a maintenance program. I used to run such a program of facility maintenance at Ford.

I've never made such a blanket statement that synthetics are always the best or the worst. They are but one answer to a series of questions. A person who knows how to design and develop a proper maintenance program can get the "best" from any fluid choice. Often, it comes down to simple dollars and cents.

Ponch's question was well crafted and contained; he wanted opinions specific to the "other" claims for syn's. I think we showed how syn's can be of benefit, but only in certain circumstances. As for extended OCIs, that is CLEARLY one of syn's advantages, especially when used with superior filtration equipment.

So, your car and bike run "better" on synthetic after five minutes of an OCI? I appologize if I seem blunt, but I prefer data and evidence to hype any day. For people who want to make an "informed" decision, that is what it takes to prove/disprove the concept. We all have our rights to our opinions, and your's are just as valid as any member here. My opinion is neither superior nor subordinate to anyones. But at some point, some of us like to put the conjecture aside and look at real facts. We choose real world evidence shown via quantifiable means over audible and tactile supposition. Some members here come to find the truth existing in evidence and data, because they find hype and rhetoric so prominent in other sources.

Perhaps I am eating the doughnuts, but at least I'm not drinking the kool-aid.
 
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This is straying off topic a bit, but why don't we use Doug's model and apply it to our passenger cars? That is, using synthetics and used oil analysis, run out our OCI's as long as practically possible. Wouldn't this save us (and our country) a lot of time, money, and oil?

Warranty would be one reason. What else?
 
In my case, it would save oil to do that. However, it costs me about $32 - $35 to change the oil and filter, and Blackstone charges $35 for a used oil analysis with TBN. Thus, it wouldn't save me any money in the long run. However, if I had an engine with a significantly larger sump capacity, things would be very different (same cost for used oil analysis, much more expensive to change the oil).

I do, however, plan to do a preliminary used oil analysis to get a better idea of my actual oil lifespan. I'm running the current fill to 6k, and will take a sample when I change it. Based on my driving patterns, etc, I'm figuring I'll be good to run 7500, but I want confirmation first. Longer than 7500 is fine by me, but slightly annoying with this vehicle (onboard OCI reminder can't be disabled, and can't be set longer than 7500 miles).
 
There are two thoughts pulling in opposit directions here.

1) OCI at some predetermined interval (this is the OEM and "Joe average" approach)
2) OCI when UOA condemnation levels are approached

The problem with #1 is that you are likely not getting the full use of your lube. The OEM is more concerned about their warranty risk than your wallet or the cost of natural resources. Further, this approach will not tell you about impending problems such as contamination (fuel, coolant, dirt). By the time you discover the problem, the warning signs have gone way past normal and you'll probably into expensive repairs. If you're not diligent about maintenance and tracking the small things like coolant loss, etc, you'll not recognize the problem and it will be "too late".

OTOH, used oil analysis have fiscal risks. Small sump equipment can just as easily be OCI'd than it can be used oil analysis, especially if you use a more expensvie service with TBN.
Example: In my wife's van, the engine takes only 4.2 qrts (I use 4.0). At $2/qrt for dino QS, and a decent filter, I can OCI for about $11. That is WAY less than the cost of a Blackstone UOA with TBN. In fact, it's about 1/3 the cost! And, how many times would I have to UOA before I'd find some reasonable OCI point? UOA at 5k miles, then 7.5k miles, then 9k miles? How many used oil analysis to pay for before the oil is worth changing? It's just simply cheaper to change the oil, and watch the coolant bottle. used oil analysis do have fantastic benefits for large fleet, large sump equipment. There, the cost of the UOA can be way less than the OCI. It makes sense to UOA; it's cheaper. And, if you can greatly extend your OCI, it get's even more attractive in regard to ROI. Just understand that used oil analysis are great tools, but they are not crystal balls allowing you to see everything.

Some bit of "hybrid" OCI concept has come out of the OLM technology. While the Ford OLM is pretty much just a mileage counter, the GM OLM in it's vehicles is reasonably accurate. It takes into accout rpm, temps, loads, idle time, etc. In both the GM cars and Dmax trucks, they have been at least in the ballpark, if not spot on, on occasion.
 
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Hi,
Jim & Dave - Yes, filtration plays a vital part, especially in extended OCIs in diesel engines

In my case (example 3) the engine's filtration systems evolved as follows:

1 - Install centrifuge, still used OEM FF filters (2). These were replaced at mid OCI (around 45-50kkms) and cut open for inspection

The centrifuges held 600g of debris and this enabled two OCIs (@ 180kkms) before cleaning

2 - Replace OEM FF filters with Donaldson Synteq FF filters. These stayed in place for the full OCI - average 90kkms (FFs filters cut open and inspected)

3 - The FF filters housings were always "clean" and the Synteq filters virtually "new" so I decided that they were simply second stage barriers to large "particles"

They were replaced with canisters containing cleanable 36micron SS inserts which were inspected/cleaned at every second OC

A used oil analysis programme was used initially to determine the OCIs. This was at 15kkms rests.
Once a reliable OCI was established used oil analysis were only done at mid point (50-60kkms) and at OC (>90kkms). They were not cost effective otherwise

Summary
An advanced filtration system and a reputable synthetic 5W-40 lubricant worked for me and was cost effective - the centrifuge units and SS filters were taken off prior to sale and retrofitted to new engines

Many of my Fleet Customers tried synthetics at double the normal OCIs but could not make them work within their establishments and reverted to mineral HDEOs. The difficulties existed in Maintenence Management, existing practices and a diverse Fleet/engine mix. There was no variance in engine life evident during these moves

Most people do not achieve any benefits from expensive synthetic lubricants (and by-pass filters) and would be best served to stay with the Manufacture's recommendations. Mineral HDEOs have always been great products and are cost effective with a great performance history.
The Brand matters very little, the correct specification is critical to engine life and durability. Conformance/compliance with API or ACEA and their "endorsement" is the best Quality basis to work from!

My experiences with "Contract Maintenance" with Scania, Volvo and especially Mercedes Benz within Commercial Fleets in the mid 1970s convinced me that correct lubricants, filtration and rigid procedures are vital for Truck/Bus Fleet cost effectiveness. The spin on effect can be achieved by enthusiastic private Owners too. Expensive syntetic lubricants and used oil analysis do NOT need to be part of the equation
 
Originally Posted By: Doug Hillary
Hi,
Jim & Dave - Yes, filtration plays a vital part, especially in extended OCIs in diesel engines

In my case (example 3) the engine's filtration systems evolved as follows:

1 - Install centrifuge, still used OEM FF filters (2). These were replaced at mid OCI (around 45-50kkms) and cut open for inspection

The centrifuges held 600g of debris and this enabled two OCIs (@ 180kkms) before cleaning

2 - Replace OEM FF filters with Donaldson Synteq FF filters. These stayed in place for the full OCI - average 90kkms (FFs filters cut open and inspected)

3 - The FF filters housings were always "clean" and the Synteq filters virtually "new" so I decided that they were simply second stage barriers to large "particles"

They were replaced with canisters containing cleanable 36micron SS inserts which were inspected/cleaned at every second OC

A used oil analysis programme was used initially to determine the OCIs. This was at 15kkms rests.
Once a reliable OCI was established used oil analysis were only done at mid point (50-60kkms) and at OC (>90kkms). They were not cost effective otherwise

Summary
An advanced filtration system and a reputable synthetic 5W-40 lubricant worked for me and was cost effective - the centrifuge units and SS filters were taken off prior to sale and retrofitted to new engines

Many of my Fleet Customers tried synthetics at double the normal OCIs but could not make them work within their establishments and reverted to mineral HDEOs. The difficulties existed in Maintenence Management, existing practices and a diverse Fleet/engine mix. There was no variance in engine life evident during these moves

Most people do not achieve any benefits from expensive synthetic lubricants (and by-pass filters) and would be best served to stay with the Manufacture's recommendations. Mineral HDEOs have always been great products and are cost effective with a great performance history.
The Brand matters very little, the correct specification is critical to engine life and durability. Conformance/compliance with API or ACEA and their "endorsement" is the best Quality basis to work from!

My experiences with "Contract Maintenance" with Scania, Volvo and especially Mercedes Benz within Commercial Fleets in the mid 1970s convinced me that correct lubricants, filtration and rigid procedures are vital for Truck/Bus Fleet cost effectiveness. The spin on effect can be achieved by enthusiastic private Owners too. Expensive syntetic lubricants and used oil analysis do NOT need to be part of the equation


Doug

I thought there was more to the story than just that, though. Didn't the vehicle regimen also include very limited idle periods (30 seconds, as I recall) and other specific driver procedures?
 
Hi,
jaj - Correct! Idling time was reduced from about 15% of total "engine on" time to around 6-7% IIRC. Drivers were under notice to shut the engine down according to the pyrometer.
This was monitored by regular ECM debriefings

This resulted in only minor idling time after climbing gradients and stopping

In many instances in Fleet Yards and at Customers Depots for instance there was zero idling time - and no wasted fuel!!!

Of course there was also the normal idling periods at traffic lights and in heavy traffic etc!

Most of the work was highway and average engine "loading" was around 70% of "on time" IIRC

I allowed the average Soot levels to rise to 3.5% when using the synthetic lubricant. Average ot OC was 3.2% and the maximum reached was 4.5%. This was only done after consultation with the Oil Company and its Additive supplier. The engine's Manufacturer was not consulted

It is also iinteresting to note that Drivers could hear the centrifuge spinning (when standing near it) and feel it's temperature to ensure it was operational. So could I and my Mechanics of course!
 
Let me clarify that I was running syn oils conectutively and during normal OCI dino was added rather than syn. I can identify this based on the increase of friction in the motor, something used oil analysis do not measure.

The focus of many of these posts are based on cost/value between dino and syn. The intent of my post was to highlight my perceived benefit in performance in my machines. If you are a person that doesn't recognize performance parameters from behind the wheel then I would say dino was made for you.

Put the machines on a dynometer and then we can talk apples to apples. This is not about used oil analysis as much as it is optimizing the performance of the machine.
 
Originally Posted By: JXW
Let me clarify that I was running syn oils conectutively and during normal OCI dino was added rather than syn. I can identify this based on the increase of friction in the motor, something used oil analysis do not measure.

The focus of many of these posts are based on cost/value between dino and syn. The intent of my post was to highlight my perceived benefit in performance in my machines. If you are a person that doesn't recognize performance parameters from behind the wheel then I would say dino was made for you.

Put the machines on a dynometer and then we can talk apples to apples. This is not about used oil analysis as much as it is optimizing the performance of the machine.



And just how do you "identify" this "increase of friction in the motor"? I agree that a used oil analysis cannot measure friction, but it does measure viscosity. How are you able to measure the "friction" of the bearings, rings on walls, cam followers, etc? How is this accomplished "from behind the wheel"? Baseless rhetoric! If you want to convince me that you can quantify the "increase in friction" in your engine, show the data to me. Show me pictures of your set up where you have a torque transducer mounted between the enginge and the transmission. Show me the evidence that you have the ability to accurately measure and record this data, and be able to rule out inconsistiencies due to set up variation. For that matter, what's the gage R&R on you seat-o-meter?

Further, I clearly and plainly discussed the example of HP increase in dyno runs. The CarCraft example; the Corvette example? I addressed "high performance" examples, but they are simply not relevant to daily diesel op's. My point was that synthetics only show a small increase of power liberation at high rpm; this make nearly zero difference to a diesel engine at 1600 rpm.

Most of the time, a light-duty diesel truck is probably running between 20% and 50% throttle. Perhaps there's a WOT run every now and then, but it is a tiny, minute fraction of the operational theater. Crusing as a steady rpm with a moderatly-heavy load the what happens to most light duty diesel drivers today. I doubt there is any sigificant statistical difference in the two oils (conv and syn) when running 65 mph down the highway pulling a boat. I know that the production variation from engine to engine is MUCH more likely to account for power differences, than the topic of a 40 grade syn versus a 40 grade dino, at 40% load steady state cruising.

Further, lubes we'd see in an engine are not completely linear in their viscus reaction. As the pressure goes significantly up, they develop a parabolic non-linear response to force, and the resultant resistance represents a loss of power by having to overcome this issue. Hence, most engines are developed with the pump, relief valve, filter media, rpm, etc all in mind to hit the biggest "sweet spot" for a given application. Diesels are easy because they have such a (relatively) narrom rpm range.

Your point is valid; there is a small gain to be found in high rpm operation when using syns.

But my point is more realistic; who runs their diesel to 5000rpm 90% of the time? No one that I know of. "Performance" is measured in many different ways. There really is no "performance" reason to run a syn in a diesel, unless you're using your rig in competition.

How about a friendly "test" of your measurement methods? We don't live that far apart, after all. Let's meet up when the weather get's nice and run some experiments. 10 different OCIs run all in the same day, in your bike. Double blind test. You ride; I'll change the oil. Let's see if you can tell me which load is dino and which is syn, after only 5 minutes of riding in each OCI. (BTW - you're buying the oil, because apparantely cost is no object to you.)
 
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You obviously haven't heard of the "engine whisperer":
http://www.enginewhisperer.com/wp/?page_id=2

"The term goes back to the early 2000’s when an Australian car enthusiast, Andrew Handmer, made a name for himself on the internet by rehabilitating engines that had become vicious and intractable due to abuse or accidental trauma."

glenn.jpg
No offense intended towards anyone here.....and....the pictured technique actually works!
 
Originally Posted By: doitmyself
You obviously haven't heard of the "engine whisperer"

ROFL @ DoItMyself...
 
Originally Posted By: dnewton3
Originally Posted By: JXW
Let me clarify that I was running syn oils conectutively and during normal OCI dino was added rather than syn. I can identify this based on the increase of friction in the motor, something used oil analysis do not measure.

The focus of many of these posts are based on cost/value between dino and syn. The intent of my post was to highlight my perceived benefit in performance in my machines. If you are a person that doesn't recognize performance parameters from behind the wheel then I would say dino was made for you.

Put the machines on a dynometer and then we can talk apples to apples. This is not about used oil analysis as much as it is optimizing the performance of the machine.



And just how do you "identify" this "increase of friction in the motor"? I agree that a used oil analysis cannot measure friction, but it does measure viscosity. How are you able to measure the "friction" of the bearings, rings on walls, cam followers, etc? How is this accomplished "from behind the wheel"? Baseless rhetoric! If you want to convince me that you can quantify the "increase in friction" in your engine, show the data to me. Show me pictures of your set up where you have a torque transducer mounted between the enginge and the transmission. Show me the evidence that you have the ability to accurately measure and record this data, and be able to rule out inconsistiencies due to set up variation. For that matter, what's the gage R&R on you seat-o-meter?

Further, I clearly and plainly discussed the example of HP increase in dyno runs. The CarCraft example; the Corvette example? I addressed "high performance" examples, but they are simply not relevant to daily diesel op's. My point was that synthetics only show a small increase of power liberation at high rpm; this make nearly zero difference to a diesel engine at 1600 rpm.

Most of the time, a light-duty diesel truck is probably running between 20% and 50% throttle. Perhaps there's a WOT run every now and then, but it is a tiny, minute fraction of the operational theater. Crusing as a steady rpm with a moderatly-heavy load the what happens to most light duty diesel drivers today. I doubt there is any sigificant statistical difference in the two oils (conv and syn) when running 65 mph down the highway pulling a boat. I know that the production variation from engine to engine is MUCH more likely to account for power differences, than the topic of a 40 grade syn versus a 40 grade dino, at 40% load steady state cruising.

Further, lubes we'd see in an engine are not completely linear in their viscus reaction. As the pressure goes significantly up, they develop a parabolic non-linear response to force, and the resultant resistance represents a loss of power by having to overcome this issue. Hence, most engines are developed with the pump, relief valve, filter media, rpm, etc all in mind to hit the biggest "sweet spot" for a given application. Diesels are easy because they have such a (relatively) narrom rpm range.

Your point is valid; there is a small gain to be found in high rpm operation when using syns.

But my point is more realistic; who runs their diesel to 5000rpm 90% of the time? No one that I know of. "Performance" is measured in many different ways. There really is no "performance" reason to run a syn in a diesel, unless you're using your rig in competition.

How about a friendly "test" of your measurement methods? We don't live that far apart, after all. Let's meet up when the weather get's nice and run some experiments. 10 different OCIs run all in the same day, in your bike. Double blind test. You ride; I'll change the oil. Let's see if you can tell me which load is dino and which is syn, after only 5 minutes of riding in each OCI. (BTW - you're buying the oil, because apparantely cost is no object to you.)


I am not laughing....
 
Regarding surface friction (metal-to-metal), conventional oils actually tend to have a higher concentration of friction modifiers than the synthetics, and you would probably have less metal-to-metal friction with conventional oil than with synthetic.

But, as Dnewton3 pointed out, sometimes people refer to viscosity as friction. Synthetics oils do tend to have a little bit lower viscosity than the conventional oils for a given grade.

So, what does this mean? Fuel economy and horsepower is dictated by the amount of friction modifiers (conventionals have more) and viscosity (synthetics have slightly lower viscosity), and chances are that you will not notice anything behind the wheel using a 5w30 synthetic vs. 5w30 conventional or 5W-20 synthetic vs. 5W-20 conventional. Even on a dyno, you wouldn't see a significant difference.

If you're actually seeing an improvement in horsepower and fuel economy using a synthetic, it's actually a bad thing because all it means is that your oil has a lower viscosity than typical for that grade and you might be experiencing higher engine wear as a result.

There is no magic way to increase fuel economy and horsepower. You decrease the viscosity and the fuel economy and horsepower goes up but so does the engine wear. Synthetics can get away with slightly lower viscosity because they can retain their viscosity longer, but that's all they can do. And, as I said, the conventionals have more friction modifiers, which tend to make up for their slightly higher viscosity. That's because the oil manufacturers need to meet the GF-5 resource-conserving (which includes fuel-economy) specification, regardless of the type of the oil (synthetic or conventional).
 
Originally Posted By: dnewton3



How about a friendly "test" of your measurement methods? We don't live that far apart, after all. Let's meet up when the weather get's nice and run some experiments. 10 different OCIs run all in the same day, in your bike. Double blind test. You ride; I'll change the oil. Let's see if you can tell me which load is dino and which is syn, after only 5 minutes of riding in each OCI. (BTW - you're buying the oil, because apparantely cost is no object to you.)


I'll gladly kick in 50 bucks for oil.
 
Originally Posted By: Gokhan
Regarding surface friction (metal-to-metal), conventional oils actually tend to have a higher concentration of friction modifiers than the synthetics, and you would probably have less metal-to-metal friction with conventional oil than with synthetic.

But, as Dnewton3 pointed out, sometimes people refer to viscosity as friction. Synthetics oils do tend to have a little bit lower viscosity than the conventional oils for a given grade.

So, what does this mean? Fuel economy and horsepower is dictated by the amount of friction modifiers (conventionals have more) and viscosity (synthetics have slightly lower viscosity), and chances are that you will not notice anything behind the wheel using a 5w30 synthetic vs. 5w30 conventional or 5W-20 synthetic vs. 5W-20 conventional. Even on a dyno, you wouldn't see a significant difference.

If you're actually seeing an improvement in horsepower and fuel economy using a synthetic, it's actually a bad thing because all it means is that your oil has a lower viscosity than typical for that grade and you might be experiencing higher engine wear as a result.

There is no magic way to increase fuel economy and horsepower. You decrease the viscosity and the fuel economy and horsepower goes up but so does the engine wear. Synthetics can get away with slightly lower viscosity because they can retain their viscosity longer, but that's all they can do. And, as I said, the conventionals have more friction modifiers, which tend to make up for their slightly higher viscosity. That's because the oil manufacturers need to meet the GF-5 resource-conserving (which includes fuel-economy) specification, regardless of the type of the oil (synthetic or conventional).


My experience with changing to Syn for the first time was in 1992 in a supercharged 4 cylinder. At the suggestion of a oil tech I selected the castrol synthetic product. My first trip on the new oil was a combined 600 miles. The car ran smoother, the mpgs increased per tank (measured over indentical trip mileage and same speed) and I felt the car generated more useable HP.

In 1993 I purchased a Jeep with 4.0L inline 6, changed it over to synthetic oil and moved to the UP of Michigan where I parked the Jeep outside daily in some very cold weather. As with the former car on Syn oil, the Jeep would start up with a quick flick of the key each and every time. Again, for a Jeep I was getting as good as MPG as anyone.

I have been pleased with the performance of the syn oils over the years as a CONSUMER of them. Having driven many high performance vehicles for my former profession, I can also say that I would hard pressed to recollect any high end performance vehicles that did not have syn oils in them.

Seems most folks that run on a track do select high end syn oils. If conventional oil had the same performance characteristics as syn oils, in the same grade then one would assume there is no longer a need for syn products, correct?
 
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Hi,
JXW - You said thia:

"If conventional oil had the same performance characteristics as syn oils, in the same grade then one would assume there is no longer a need for syn products, correct?"

IME - yes correct! The word "need" being the operative!!
 
Doug Hillary said:
Hi,
JXW - You said thia:

"If conventional oil had the same performance characteristics as syn oils, in the same grade then one would assume there is no longer a need for syn products, correct?"

IME - yes correct! The word "need" being the operative!!


[/All lubricants fall into one of three categories: liquid (oil), semiliquid (grease), and solid (graphite). All three are derived from vegetable, mineral, or synthetic base stock. However, were these raw materials alone used to lubricate modern, high-precision machinery; they would quickly overheat, catch fire, evaporate or emulsify. To guard against this, all lubricants are doctored to a certain extent - processed to remove impurities and bolstered with chemical additives. Synthetic lubricants, however, are manufactured specifically to stand up to the severe conditions under which conventional oils might falter. They are designed to possess viscosity characteristics superior to those of mineral oils. The resulting lubricants have a molecular structure that is tailored to meet and often exceed manufacturers' criteria for high-performance engines.
quote]
 
JXW - As far as the need for synth, there is definitely need, but the point is that a lot of people use it in applications where it isn't needed.
 
Hi,
JXW - Really - an unidentified quotation - wow! This is a HDEO Forum - HDEOs are specifically Commercial lubricants!

Please refer these 'quoted' comments to CAT etc - especially as they and many other engine Manufacturers would need to rewrite much of their literature and lubricant specification material, and trash their own (and others) well reseached development material!

Please reread your own statement:

"If conventional oil had the same performance characteristics as syn oils, in the same grade then one would assume there is no longer a need for syn products, correct?"

Unless specified by the engine's Manufacturer synthetic HDEO lubricants are not cost effective in normal operations - in the "whole of life" scenario!
 
Here's something anecdotal and semi-related to toss in.

A few years ago, I tested three gear oils; A common mineral 85W90, a straight mineral 90 and synthetic 75W90. The brand names are immaterial but you can find them on the attached link. Since friction creates heat, I thought measuring oil temps over a specific course with a specific load would be an indicator of the "slipperness" and friction reducing qualities of the oil. After all, the oil companies advertise such things as benefits. There was no surprise that the oil temps were lower on the syn oil vs the mineral 85W90 but, surprisingly, the straight 90 beat them both. How? Additives! It had a heavy load of a moly-like additive that was able to take a Gp II mineral oil into super slippery territory.

My point is that the advancement of lubricant refining and additives have brought "oil ordinaire" (Gp II+) and what we have long regarded as "synthetic" (Gp IV an V) closer together. Don't forget that Group III oils are now considered "synthetic." Personally, I'm not all that caught up in those distinctions. I look at them as choices from which I can pick the most applicable characteristics according to application and need vs cost.

Yeah, some people buy higher up on that food chain than they need. That's fine but often hard to justify with logic given how little most of us actually know about the ongoing internal engine conditions of our individual vehicles. That's one reason why these discussion often get heated and irrational.

Axle Test
 
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