Does conventional oil protect better?

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Honest question gents...I've been pouring over UOAs and while there has been far less on conventional, it appears conventional oils produce less wear metals etc. Is it possible they protect better albeit for a shower oci?
 
Originally Posted By: Doublehaul
it appears conventional oils produce less wear metals etc.

Based on what?

A single $30 UOA is not a good indicator of engine wear.
 
What are the engines under question?

I'd think a conventional getting changed every 3k and in an old school low stressed engine would show low issues. Even on longer drains, something old like an EFI GM 350 or Ford 4.6 should show pretty much nada--these were long life motors that were not very picky.
 
Comparing different oils in different engines operated in different environments and different operating conditions is not a good comparison. Not to mention that a UOA isn't a proper way to determine comparative wear rates no matter what.
 
Perhaps the UOA for conventional oils are more common on older, broken-in engines that are producing very little wear metals?

To support that synthetics SHOULD produce less wear metals is the fact that new engines will take longer to 'break-in' with full synthetics versus conventionals.

Regardless, the vast majority of owners who take the effort to do UOA and post on BITOG are very vigilant about maintenance and would tend to have engines displaying very low wear metals - all things being equal.
 
"Protect" better against what? Oil has a multifaceted job.

Low group blends can have better inherent lubricity, but if your rings are gummed and sticky that's not a good tradeoff.

Animal fats can indeed be better lubricants than additised, refined Mineral oil in certain applications.

It is becoming MORE apparent to me that todays highly-stressed, complex engines need the best you can give them, and this includes quality gasoline. Poor running will produce excessive wear regardless of relative "quality" of lubricant chosen. My humble rogue 4 cylinder has more horsepower than my 5 liter Mustang "H.O." V8 from the mid eighties!

cheers
 
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Over in technical papers forum there is an ongoing discussion about wear metals, especially upper cylinder wear on straight SAE 30 HD vs multi-viscosity oils on cold start. I tend to agree with the findings from my personal observations.

It has to do with the inclusion of viscosity index improvers not protecting as well as straight oil for condensed moisture from cold cylinder wall iron and by-products of combustion forming on same.

Then there is the "drain-off" issue with some synthetics. They have lower surface tension than mineral oil. So they can have a thinner residual film after setting for a prolonged time (days) so there is less cushion at cold start. Dino oil have a higher surface tension which means they are better at maintaining capillary fill and a thicker residual oil film.

Whether or not that means anything to your motor is another question... If the motor is built for it and the clearances are still tight enough, it will make no difference. If it's an old school motor or has a lot of miles on it, it may make a difference. Listen on cold start and it you hear low frequency sounds (not just valve ticking), chances are your residual film is not quite thick enough.

All of this is one reason Chevron Delo 400 was the first HDEO to post a 1,000,000 mile motor in fleet operation. It was just really well refined dino oil. It has gotten better over the years. It is my go-to oil to quiet noisy engines. It generally shows very little wear metals.

But it's not right for all applications. Lots of modern motors would not be all that happy on Delo ...
 
On air cooled engines, synthetic oils will tend to run 5-10 degrees cooler.

A cooler engine is a sign of less friction. Less friction means less wear.

Synthetic oils SHOULD offer slightly better wear resistance over the life of the engine.
 
Todays conventional oils aren't like the oils of the 1960's. Then what is syn oil these days?
 
Synthetic oils SHOULD offer slightly better wear resistance over the life of the engine. [/quote]

Yes that may be so but how long are you keeping your car or truck and will you ever notice any advantage? Here in western MA its not the engine I worry about its the rust and wear and tear on the rest of the car or truck that is the big issue. I put around 30K a year on my rides and I don't seem to get over 200,000 miles before rust and other issues take there toll. Any quality conventional oil should have no problems getting me to 200,000 miles.
 
Synthetic oil just empty's your wallet quicker. The power marketers have over some peoples mind is scary. Sell them something they don't need and make them believe a lot of hype and they will buy it. Snake oil pushed by Amsoil, and Mobil. It's all about making money. Always offer a more expensive product and convince the customer it has benefits. It's called up selling. Most people that use synthetic get rid of their engines before any magical mythical benefits would ever show up.
 
Originally Posted By: sprite1741
Synthetic oil just empty's your wallet quicker. The power marketers have over some peoples mind is scary. Sell them something they don't need and make them believe a lot of hype and they will buy it. Snake oil pushed by Amsoil, and Mobil. It's all about making money. Always offer a more expensive product and convince the customer it has benefits. It's called up selling. Most people that use synthetic get rid of their engines before any magical mythical benefits would ever show up.


I often feel the same way ... Frankly I would really like to see a modern high teck engine run on a cheep conventional oil (ST or Formula Shell) run at a reasonable change interval and see if it would really make any difference over a millage time like 150-250K. My bet is even if there is a difference it would be small and it really wont matter other then the fact I would be spending less $ on oil changes.
 
Originally Posted By: sprite1741
Synthetic oil just empty's your wallet quicker. The power marketers have over some peoples mind is scary. Sell them something they don't need and make them believe a lot of hype and they will buy it.

..... when they often replaced the synthetics at 5K or thereabout on a typical NA multiport injection.
 
If the parts are kept separated what can the difference be? Below 0*f cold start and possible the length of the oil change interval. Lets say it could depend upon the application.
 
I hope you guys are talking about low wear high mileage motors,. If you were talking about motors that don't typically last more than 30,000 miles then you would be dead wrong. Synthetics OBVIOUSLY work better than dino oils in things like race engines, hot rodded engines, and dirt bikes. That is enough to put me over the fence on the dino vs synthetic argument. When I see the results in engines that typically don't last very long, synthetics are an obvious choice. I take that expereience and apply it to passnger cars where I will never live to see the final results. Sure, it is not 100% scientific proof that synthetics work better, or they may never pay for themselves. But is is not like a I am basing a decision on "marketing hype". There is real expereience that goes along with it. I once posted a thread about all the common engine failures I had seen in street cars that are related to damage from oil breaking down. These were real world observations based on years of experience. Lots of cars end up with issues directly related to poor lubrication. Ever heard of a turbo bearing failure? Ever heard of a stuck engine valve or stuck piston rings or a failed crankshaft oil seal? These are lubrication failures that are alleviated by modern synthetic oils. And lets not forget that synthetics come with the better additive packs in the oil. Try finding a conventional oil that comes with a top of the line additive package anymore. There is plenty of evidence that synthetic oils work better than dino oils if you lok for it. Sure there is "confirmation bias" in my approach, I am looking for improvements so I find them. Nonetheless to even HINT that there is no evidence synthetics work better than dinos is just plain wrong. There is plenty of evidence, whether it is worth it to you in your application is another story.
 
Who has ever got more for their trade in from a dealer because they used syn. I have a tow truck friend that says he tows in more cars that are run on syn oil because they are told that they don't have to change the oil for 10,000 to 15,000 miles at a time. A lot of them are run out of oil because nobody checks the oil in them.
 
And lots of people are idiots.

I run synthetic for its rated 10k OCI. I check the oil every few weeks. I do mostly highway so the oil is likely good for even more miles--but I call it "good enough". I can do 10k of whatever I want at that point--hard driving, city, whatever. No worries.

Now that I've wisened up to oil rebates, I'm driving my oil cost down. For example, the Mobil 1 that is sitting in my basement was $2/qt. The PP I currently have in the sumps was even cheaper. If I wanted to be even cheaper I'd do a UOA and find out if I could go longer.

For the record I do anticipate -20F starts in the dead of winter where I live. There is almost always a week of less than -10F cold starts, and plenty at below 10F. 5W would probably be fine; but why not 0W for the same cost?
 
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