Synthetic or Conventional motor oil in Kubota diesels

GeoHorn

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Another tall tale...... 45 years of auto repair and I still have never seen one single case.

And a test.....
That’s hardly reason to claim “tall tale”.
I really like “Project Farm” and his tests. Notice that he specifically stated that this video is only ONE test…and asked for input from others.
I agree his old blue tractor seems to have a good crankshaft seal. That’s NOT what I meant by my previous post… I never claimed synthetics cause seal leaks.
My 50 years of auto and aircraft experience has seen several cases of leaks at other gaskets and seams in engines that were converted to synthetic. I did NOT say it WOULD cause leaks. I said “don’t be surprised”… and I posted that largely on anecdotal comments by others who have reported that to me. (It may very well be that the synthetic they converted-to was lower viscosity oils and might naturally be more likely to leak than higher viscosity oils regardless of type… Anyway, just “don’t be surprised”.…)
 
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lmichael

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Another tall tale...... 45 years of auto repair and I still have never seen one single case.

And a test.....
I just wish he hadn't added snake oil to it. In any case it proved the point. Also when I began using Mobil 1 it was only available in one grade (5W-20) it went into my 69 Caddy with a 472 ND my 69 Moto Guzzi V7 motorcycle. Obviously both engines were always on dino juice because M1 had just been introduced. No oil leaks developed and no noises or damages. When I sold the Guzzi I installed M1 in my BMW replacement. Again no issues. Many of my friends also began using it too. None of them had issues either. But, it should be noted we all were very much into keeping our vehicles in sound shape and sticklers for maintenance. I imagine if you stuck a quality lube like M1, Rotella T-6 or such in an engine that was not cared for yeah it might uncover some issues that were there anyway
 

GeoHorn

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So your saying subpar gasoline which had lead added to it so it didn't knock is 'real' gasoline? Interesting....
Is that what you concluded from my earlier post? That‘s NOT what I said at all.

I was only stating that aviation gasoline is more like traditional gasoline from years-gone-by…. not the “paint thinner/aromatics with ethanol” that we see at the gas pumps these days. (In fact, the basic gasoline which makes up avgas is already 91-94 octane PRIOR to the addition of the TEL. It is NOT “subpar” by any stretch of the imagination. (The TEL brings it’s octane up to 100+ minimum.)

Much of the aviation market does not require the TEL in the gas at all but it’s added by the refiners to meet the needs of higher-performance aircraft engines and those who own low-compression engines simply have to put up with that nasty lead…. and is why I refuse to use synthetic in my airplanes. To expand on that, the aviation market subsequent to the Mobil-1 fiasco decided to sell more product by blending syn with conventional oil in a “semi-synthetic” product…claiming it has the features of both types. Maybe…maybe not… I still use the stuff my engines were certified with…..conventional oil…. not oil that claims it has reversely been certified for my engine. YMMV)

I was also pointing out that avgas has TEL in it. TEL is a nasty that gets down into the oil sump and creates that grey sludge we used to see…. it is LEAD… and it’s abrasive and contributes to WEAR. One of the major reasons modern auto engines last 200K+ miles when pre-74 engines were commonly found to be “worn out” at 75K was the LEAD in the pre-74 gasoline and the nasties it makes down in the oil sump that causes wear and corrrosion. (Amoco used to market lead-free “white gas” and advertised it made engines last longer…. and they were correct! The rest of the industry finally agreed with them.)

My point was that Mobil found that synthetic oil cannot scavenge lead and other nasties as well as conventional oil. That is the bottom line.
 
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mattwithcats

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Your dealing with two different topics,
The first, oil type, conventional, semi-synthetic, or synthetic.
The second, oil weight, 10W-30, 0W-40, 5W-40, or 15W-40...

I use conventional 15W-40 in big bones, where you need a pail or more (20+ quarts)
The difference is $50 for a pail of conventional verses $100+ for synthetic 15W-40
I make my own semi by adding 2-4 quarts of 0W-40, capacity is 22-24 quarts on the truck.

Small bones come in air cooled, and water cooled.
I use semi-synthetic 10W-30 in most air cooled, because it gets changed out at 50 hours, and the cost.
Air cooled engines tend to be super tough on oil.
Generators are the exception, they get 0W-40...

small bones water cooled gets 0W-40, because the blocks are small,
and I want as little starting wear, and stress on the block as I can get.

Lately I have had so much 0W-40 the air cooled stuff has been getting fed that, now that I have run out of 10W-30.
 

GeoHorn

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I can understand your puzzlement. The explanation I can offer is that as a maintenance advisor to a type-club group I’ve occasionally received such reports from owner/operators who switched to synthetic and discovered leaks/seepages where none previously existed. I don’t have an explanation… only a report to make of it. Perhaps during the switch a lower viscosity oil was used, as synthetics are commonly found in lower viscosities than conventionals… but that’s only a possibility…as no accurate database exists of those who switch oil types, as you might imagine….it’s not a scientific expedition. It’s why I said “don’t be surprised”… It apparently happens and word gets out without much scientific basis as to why.
 

TheOldHokie

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I can understand your puzzlement. The explanation I can offer is that as a maintenance advisor to a type-club group I’ve occasionally received such reports from owner/operators who switched to synthetic and discovered leaks/seepages where none previously existed. I don’t have an explanation… only a report to make of it. Perhaps during the switch a lower viscosity oil was used, as synthetics are commonly found in lower viscosities than conventionals… but that’s only a possibility…as no accurate database exists of those who switch oil types, as you might imagine….it’s not a scientific expedition. It’s why I said “don’t be surprised”… It apparently happens and word gets out without much scientific basis as to why.
So in other words its the typical unsubstantiated FUD (Fear Uncertainty and Doubt) that is almost always floated in these debates.

Dan
 

mikester

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Generally I like buying the best priced name brand synthetic on sale at Canadian Tire whenever I need to change my motor oils. If you stick with the service intervals I don't think it matters which name brand you use.

I buy non-synthetic yamalube for my bike because momma yama promised a lifetime engine warranty if I do. Dino oil can't be all that bad if an OEM is willing to warranty an engine lifetime with it.
 

TheOldHokie

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Wonder if she's using the right grade?
[/QUOTE]
If she would like to change my oil she can use whatever grade she prefers.

Dan
 
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Mark_BX25D

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Synthetic or Conventional motor oil in Kubota diesels
Yes! Absolutely!


There. Everybody happy now? :love:


(Hey, if you are still not, maybe consider this: synthetic oil made 40 years ago when they were new on the market just might not be the same animal 40 years later. It's at least possible that lessons were learned and that changes were made.)
 
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Nicfin36

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(Hey, if you are still not, maybe consider this: synthetic oil made 40 years ago when they were new on the market just might not be the same animal 40 years later. It's at least possible that lessons were learned and that changes were made.)
I would bet conventional motor oil is not the same animal as it was 40 years ago either. :)
 
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TheOldHokie

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Yes! Absolutely!


There. Everybody happy now? :love:


(Hey, if you are still not, maybe consider this: synthetic oil made 40 years ago when they were new on the market just might not be the same animal 40 years later. It's at least possible that lessons were learned and that changes were made.)
I am happy🥳🥳 i would also add the same is true of conventional oils. The Wolfs Head MS/DG Grandad poured into the old Ford tractors could not hold a candle to a modern SM/CF oil in any application. If the API service class meets or exceeds the OEM specification its good to go.

Dan
 
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GeoHorn

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So in other words its the typical unsubstantiated FUD (Fear Uncertainty and Doubt) that is almost always floated in these debates.

Dan
only as regards “don’t be surprised” if leaks develop in a switch
 

number two

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Kubota delivers them with 10W30 oil.
Who am I to disagree with them?
It's what I use,and I'm sure my equipment will outlast me!
Good Luck!
 
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BruceP

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Kubota delivers them with 10W30 oil.
How do you know that?

I guess it is possible the engines are shipped 'dry' from Japan and filled at the dealership. In which case, it is not Kubota who is pouring in the delivery oil.

Are you aware that some engine makers use 'break in oil' for the first fill? This is one reason the first oil-change is often timed differently from all the subsequent ones.

Infact, changing out the initial fill too soon may interfere with the intended break-in process.
 

mcmxi

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Since I don't have a degree in chemical engineering and don't work at a refinery, I tend to defer to those who have a vested interest in how an engine performs since they typically research this stuff ad nauseam. I'd never heard of Schaeffer's Oil until three years ago. I run Mobil 1 in my '98 Jeep TJ and have for close to 20 years (I've had it for longer) and it has never leaked oil. I've also used a lot of Amsoil products over the years, but when I bought a chip and programmer for my '02 F250 7.3L Super Duty I asked the owner of DP-Tuner if he recommended a specific oil. He told me that the only oil he recommends to his customers is Schaeffer's fully synthetic.

He has a vested interest in how his customer's engines perform when using his products for obvious reasons so I was happy to defer to his opinion. Of course, it's possible that he's a part owner of Schaeffer's or has some other motivation, but since engine performance is correlated to some degree to engine oil, and his business is all about performance, reliability and longevity I tend to think that he's recommending a product that although not cheap, increases the likelihood of happy customers who not only recommend his products, but also come back to buy more products, just as I have done.

I work in the firearms industry and these kind of debates rage all the time. When it comes to opinions on products I don't look to the guy who spent $3K on an optic and goes to the range once a month, sits on the bench the whole time and then is on a forum ridiculing others for not buying what he bought. I tend to look at someone who's choice is far more meaningful whether they're a serious hunter, LE, military, contractor, etc.

So when it comes to tractors, machinery, oil and such, I'm more likely to put stock in someone who makes a living with their equipment, for whom maintenance, maintenance costs, downtime, longevity, reliability etc., aren't simply topics for an internet forum. For the record, I don't make a living with my tractor, can deal with downtime, but I also like to take care of machines that I own the best way I can. I get satisfaction from using things hard but also maintaining them to the best of my ability which means using the best products I can afford.
 
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GeoHorn

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The U.S. Military uses ordinary petroleum (conventional) motor oils (MIL-PRF-2104) in the majority of vehicles and uses synthetic (MIL-PRF-23699) in turbines such as aircraft and Abrams tanks, etc.
For long-term-storage vehicles they use conventional storage-oil (MIL-PRF-21260).
All new military vehicles are delivered with the same MIL-spec oil they are expected to be run with in the field…. which is predominantly conventional motor oil (MIL-PRF-2104), I.E. no special “break-in” oil.)

The only major deviation is arctic use in which semi-synthetic (blend) (MIL-PRF-46167). This according to the quartermaster at local Texas Nat’l Guard unit.

It’s probably worth acknowledging the military uses the lowest bidder for supply but that bidder MUST meet the Mil-spec called for. (it only means the name-brand may change but must remain compatible with whatever has been previously used.).

What individual participants in these forums uses is likely whatever their wallet can afford which also agrees with personal opinion and makes them feel good. The mfr’s specify “minimum” requirements which meets their expectations for warranty-liabilities.

If you like paying for name-brand prescriptions then have at it. I usually settle for generic equivalents and have had satisfaction with them.
 
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mcmxi

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The U.S. Military uses ordinary petroleum (conventional) motor oils (MIL-PRF-2104) in the majority of vehicles and uses synthetic (MIL-PRF-23699) in turbines such as aircraft and Abrams tanks, etc.
For long-term-storage vehicles they use conventional storage-oil (MIL-PRF-21260).
All new military vehicles are delivered with the same MIL-spec oil they are expected to be run with in the field…. which is predominantly conventional motor oil (MIL-PRF-2104), I.E. no special “break-in” oil.)

The only major deviation is arctic use in which semi-synthetic (blend) (MIL-PRF-46167). This according to the quartermaster at local Texas Nat’l Guard unit.

It’s probably worth acknowledging the military uses the lowest bidder for supply but that bidder MUST meet the Mil-spec called for. (it only means the name-brand may change but must remain compatible with whatever has been previously used.).
I worked as a research engineer on US Military funded programs for 10 years, mostly material selection and corrosion mitigation. Equipment readiness numbers are so unbelievably bad that I put very little stock in anything "mil spec" or many of the decisions made when it comes to selection. I have far more confidence in a business owner who is directly accountable for the decisions that he or she makes. Just my opinion based on 10 years of research projects, reports, papers, conferences, endless meetings, and such.

I really hope that it's an even worse state of affairs over in China!
 
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GeoHorn

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For all the miserable opinions about China…. it may be useful to remember they are EXCELLENT at COPYING ANYTHING….and that we’ve sent them Examples of EVERYTHING we wish to purchase and they’ve acquired access to lots of things we never wanted them to have. They share that info (for a price) with Russian, North Korea, and anyone else who wants to buy it.

What WE are screwing up on …. is we have NO NATIONAL FOCUS on what truly threatens our security… our own home-brewed terrorists and conspiracy-theory-spreaders….which are being supported by our enemies and facilitated by social media “instantanea.” … which has no proper checks-and-balances. We’ve forgotten what we all were taught in elementary school… “YOU CANNOT BELIEVE EVERYTHING YOU READ!”

Back to regular programming….