Using HDEO's in Gasoline Engines

Originally Posted by gfh77665
I firmly believe PCMO is better for typical gas engines. If HDEO was really somehow better for gas engines, then why wouldn't all the majors simply convert their production to HDEO only? Why spend all the R&D efforts and dollars to make the great PCMO's we have now?


"Resource conserving" and cafe fleet avg fuel economy requirements.
 
HDEOs in gas engines should have dual diesel/gas engine quality ratings - API or ACEA or both -and a suitable viscosity.
 
Originally Posted by LeoStrop
I guess he didn't bother to look on the UOA's posted here using rotella in gas engines.


It was just a shill post by Amsoil attacking Rotella, didn't Amsoil recently release a product to directly compete with Rotella T6?
 
I have been running Rotella T 15w40 in my classics; mid '60s high compression big block V8s with flat tappet camshafts.
This is due to the reduced Zinc in gasoline oils to about 850 ppm. I think 10w30 is higher, not sure.
Rotella T was closer to 1200 ppm, but has been further reduced in current blends.
The original L36 427 in my Corvette (aka numbers matching) makes the car more valuable to collectors.
Personally I could care less.
But I do not want a blown original engine.

I am now forced to use expensive oil with requisite Zinc.
If I ever pull that engine apart again I will stab a hyd. roller and be done with it.
Same with the Oldsey.
 
Quote

Subaru enthusiasts that this specific oil does not function well at all in Subaru direct injection engines. Go over to NABISCO and one of the first threads you'll likely come across states this very clearly in the first post.


Does that website use cookies?
 
I think there is some truth in Reason 1 about ZDDP types.
Reason 2: I'm not sure what anti-foaming differences there are between HDEO and PCMO.
Reason 3: I firmly believe he is correct that detergents and dispersants are formulated differently in HDEOs and PCMOs. However I am not sure I agree with what he said about poor ring seal.
Reason 4: if he is talking about Rotella T6 5W-40, then yes I agree that it loses a detectable amount of viscosity. That's to be expected of most 5W-40 oils.

I think he has some valid claims but he attributes too much importance to the differences between HDEO and PCMO. It is true that they are formulated differently and that includes dual use oils vs PCMO-only oils.

This 2016 document shows some of the differences between the two types of motor oil: https://www.atc-europe.org/public/D...t%20Additives%20Use%20and%20Benefits.pdf
 
Yes there are different types of ZDDP and HDEOs use a different type to most PCMOs.
The ZDDP that HDEOs tends to deplete more slowly versus the type in PCMOs is designed to deplete more rapidly and aimed towards maximum wear protection.

However in practice both types seem to do a perfectly good job of protecting flat tappets and such from wear.

Dual rated HDEOs are a very good option for older gasoline engines, the one i use which is Shell Rimula R4X 15W-40 is a Dino Group 1 HDEO with around 1250ppm of ZDDP and i have recommended it to various friends who also use it without problems.
 
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Everything that is stated there is factual. I can attest to the foaming issue with Rotella at sustained high rpm. Does any of it make a difference in a stock daily commuter that never goes WOT or >3k rpm? Probably not. Does it make a difference in a race engine that sees sustained WOT and >7k rpm? Absolutely.
 
Originally Posted by The Critic
A friend of mine shared this post with me.

Thanks for sharing.
I worked on class 8 diesel trucks for 30 years. I never thought diesel oil in gas engines was a good idea (although I did use it because it was free). For those who claim great UOA's, that is only showing the oil is holding up well. Not the engine.
My opinion is dual rated HDEO's are either a poor diesel oil (most likely) or a poor gas engine oil.
 
Originally Posted by ka9mnx
Originally Posted by The Critic
A friend of mine shared this post with me.

Thanks for sharing.
I worked on class 8 diesel trucks for 30 years. I never thought diesel oil in gas engines was a good idea (although I did use it because it was free). For those who claim great UOA's, that is only showing the oil is holding up well. Not the engine.
My opinion is dual rated HDEO's are either a poor diesel oil (most likely) or a poor gas engine oil.



It does show condition of the oil, but lower wear metals means better wear in my book.
 
Originally Posted by ka9mnx
Originally Posted by The Critic
A friend of mine shared this post with me.

Thanks for sharing.
I worked on class 8 diesel trucks for 30 years. I never thought diesel oil in gas engines was a good idea (although I did use it because it was free). For those who claim great UOA's, that is only showing the oil is holding up well. Not the engine.
My opinion is dual rated HDEO's are either a poor diesel oil (most likely) or a poor gas engine oil.


Exactly. Usually the more applications any single particular oil or fluid is certified for, the less it excels at each application. It's the same with people. If you ask an employee to do one task 20x each day, they'll be far more efficient and productive at it than if you asked them to do 20 different tasks each day.
 
Originally Posted by ka9mnx
Originally Posted by The Critic
A friend of mine shared this post with me.

Thanks for sharing.
I worked on class 8 diesel trucks for 30 years. I never thought diesel oil in gas engines was a good idea (although I did use it because it was free). For those who claim great UOA's, that is only showing the oil is holding up well. Not the engine.
My opinion is dual rated HDEO's are either a poor diesel oil (most likely) or a poor gas engine oil.


Just search for HDEO on this forum and you will find dozens if not hundreds of first hand accounts of how HDEO has worked perfectly during thousands of miles in many different gas engines.
 
Originally Posted by FordCapriDriver
Originally Posted by ka9mnx
Originally Posted by The Critic
A friend of mine shared this post with me.

Thanks for sharing.
I worked on class 8 diesel trucks for 30 years. I never thought diesel oil in gas engines was a good idea (although I did use it because it was free). For those who claim great UOA's, that is only showing the oil is holding up well. Not the engine.
My opinion is dual rated HDEO's are either a poor diesel oil (most likely) or a poor gas engine oil.


Just search for HDEO on this forum and you will find dozens if not hundreds of first hand accounts of how HDEO has worked perfectly during thousands of miles in many different gas engines.


UOAs don't tell the whole story. I tore down an engine recently that showed
You're also talking about engines that aren't taxing the oil. Daily commuters, engines that spend more time cruising or idling in traffic than wide open throttle and high rpm.
 
^good point on UOAs and their limitations. I never get too concerned about small differences in ppm of wear metals. Catastrophic wear could be occurring with low ppm due to the larger particle size not being detected by a standard oil analysis.

Also correct about sustained high RPM vs hitting redline several times a day in your DD.
 
i just finished watching a video on the Hagerty website about Shell motor oils. Sure it was an infomercial. It was moderated by Hagerty with two Shell engineers. The engineers were adamant that Rotella T-4 15w-40 was the best oil for older cars with flat tappets, muscle cars, etc. Sure they are biased but why would they tell customers to use their HDEO in passenger car engines with flat tappets if it would harm the engines? They could have just said that they did not make oils for cars that old.
 
Originally Posted by Building3
i just finished watching a video on the Hagerty website about Shell motor oils. Sure it was an infomercial. It was moderated by Hagerty with two Shell engineers. The engineers were adamant that Rotella T-4 15w-40 was the best oil for older cars with flat tappets, muscle cars, etc. Sure they are biased but why would they tell customers to use their HDEO in passenger car engines with flat tappets if it would harm the engines? They could have just said that they did not make oils for cars that old.


They sure wouldn't be risking openly recommending one specific oil for a certain application if they didn't believe it was a good choice.

Perhaps on paper things may suggest that HDEOs can foam at sustained high revs.

But i have never seen foaming with HDEO personally, i sometimes go out for a spirited drive in my Escort up the mountains, this usually means about half an hour ish of sustained 3000-4500rpm.

I remember having read something about foaming with HDEOs and wanted to see for myself if the oil would foam.

I shut the engine off after about half an hour of fairly high sustained revs and checked the dipstick, no foaming i could see.
 
I recently did a short run with Morris Lubricants HD4 15w40 in our Mondeo ST with a Duratec30, admittedly I also had 6oz of Seafoam in the mix too.

I took it up to Mid-Wales and kicked it's head in, regularly running it upto ~7200rpm. I stopped at one point to fill up with fuel and checked the oil level and there was no signs of aeration or foaming.
 
i use hdeo in my gasoline powered vehicles. some have dual ratings like delo. others like shell, don't. but, i don't care. cars run great. YOLO
 
Originally Posted by Ignatius
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Reason 2: Anti-foaming. Also referred to as air release, the oil has to release air pockets generated during friction and movement. Rotella is not very good at this, and that's OK when you are running a Detroit Diesel with a 2100RPM redline or even a 6.7 Powestroke with a 3400RPM redline (where the anti-foaming starts to become a bigger issue), not so much when you're running a Subaru FA20 with a 7400RPM redline. Under extended use, this can eventually aerate the fluid enough to cause catastrophic failure, or at minimum power loss.


Funny they made reference a Subaru DI engine using Rotella T6. It has been well know for at least 5-6 years that despite Rotella T6's cult following among Subaru enthusiasts that this specific oil does not function well at all in Subaru direct injection engines. Go over to NABISCO and one of the first threads you'll likely come across states this very clearly in the first post.

Most people using Rotella T6 in a Subaru engine are usually doing so in a port injected WRX or STi, often with a cat deletion mod. It has a very solid track record of producing excellent results under those circumstances.


Yeah, I've never heard of foaming issues in WRX's and I've been on NABISCO since way before it was NABISCO. And you're right about the DIT. 2015+ WRX owner's have largely moved away from the old school Rotella and on to ACEA C3 oils. A few folks are still running high SAPS oils in DIT's and most of those are modified (I understand that TGV deletes mitigates intake valve deposit issues). Maybe this person has not really done their homework before making some of these comments?
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This is one of my favorite posts here about HDEO's in gasoline engines:

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Dennis - I first experimented with HDEos in petrol engines in Europe in the early 1960s when working in Copenhagen for Caltex-Chevron in a Technical position

This was prompted by various experiences, excessive engine deposits in certain engine families, "poor" petrol engine lubricant standards and motivated by the results coming out of MB and Porsche. Porsche FF in the 1950s-1960s was a Shell HDEO

I've used HDEOs in petrol engine ever since - for nearly 50 years!

This was confirmed by extensive lubricants field testing for a number of Oil Companies over several decades

Modern appropriately classified lubricants as recommended by the engine's Manufacturer have almost effectively negated their use in petrol engines today IMO

My dealings and comparisons of HDEOs started in the early 1960s. I was always motivated by the MB and CAT lubricant specifications at a time when very few existed. I've always found that Shell and Delvac products produced the cleanest engines as the end result.
 
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