Synthetic or Conventional motor oil in Kubota diesels

[Mark_BX25D]

Just saw (for the first time) T-6 15-40 yesterday.

Interesting. It's dirt common around here. I run it exclusively.

 

[lilguy]

I had 2 early 80s Kubotas, a L2250 for loader work and snow removal, a B8200 HST for mowing grass. Ran Mystic 10w30 dino oil in them for 34 years and several thousand hours. Using it still, now a blend, in my new rigs. Changed both every fall, neither tractor dripped any oil when sold. It’s what I’m use to and it has worked.

 

[DustyRusty]

I have read all 7 pages, and have learned nothing more than I already knew. Change oil regularly, and use the best oil that you can find with the rating that is set by the manufacturer.
I'm down to my last case of oil, so I will need to go to the store and buy some more...

 

[Dennis.D]

I would like to use Kubota oil in my Kubota, but they don't offer synthetic oil for the motor. They ONLY offer synthetic for hydraulic fluid (super udtII) and they very defiantly tell you not to use anything else. I do only use Kubota filters. I'm a believer in synthetic oil is better. Especially since my Gr L6060 has a turbo. I just purchased a Kubota zero turn. It has a Kawasaki air cooled engine and go figure they don't offer synthetic oil for the Kawasaki either. They again say the manufacturer doesn't recommend it their oil (Kawasaki) has more ash and is better for the engine. I have a Skidoo 850 2 stroke and they only offer synthetic 2 stroke (@$60 per gal) in the skidoo brand oil and again they advise you strongly against using any thing else. I remember when Harley didn't offer synthetic oil and they said it wasn't recommended in Harley's. Then years later they offered synthetic oil with the Harley name on the bottle and now you can use the same oil in the engine, primary and transmission. I'm beginning to see a pattern that the manufacturer has a personal (money) interest in selling oil with their name on it. So I will use synthetic oil, with the proper specs for each engine. I will support the manufacturer if they offer synthetic, but will go with synthetic either way.

 

[85Hokie]

I would like to use Kubota oil in my Kubota, but they don't offer synthetic oil for the motor.

Remember - Kubota makes the parts - others make the oils. Nothing wrong Kubota oil, but IF you wish to use synthetic, then do so. Kubota's oil is just good ol fashion dyno oil - aint nothing wrong with it, BUT when you want to turn that engine over up there in the cold state of Maine - I would be using synthetic IN a new york minute. Quick like and in a damn hurry.

As someone posted a bit ago - "been using 10w-30 for 30 years in my tractor and never had a problem" - ANY current oil is a lotttttttttt better than oils 20-30-50 years ago. BUT - IT HAS BEEN proven in every day........ the earth IS ROUND, 4+ billion years old and SYNTHETIC is just better!!!

 

[fried1765]

So in the last six months I have bought two new units with Kubota diesels in them Grasshopper 325D and a MX- 6000 tractor. I grew up in the oil business and have always used Mobil Delvac or Shell Rotella. I have a couple older diesels that I use conventional oil in but the rest of the fleet on the farm I use Synthetic. So I said to the Grasshopper dealer conventional or synthetic in the Kubota he says conventional only. I said to the Kubota tractor dealer conventional or synthetic he says conventional in the Kubota's, I am close to fifty hours on each of them so should I use conventional or synthetic in them. I will probably change the mower at 50-100 hours after the first oil change and probably 100 hours on the MX-6000 after the first oil change.

I think the difference is TOTALLY overblown (by the marketers of synthetic oil).
Synthetic likely does make a starting difference in cold weather areas though.

 

[85Hokie]

I think the difference is TOTALLY overblown (by the marketers of synthetic oil).
Synthetic likely does make a starting difference in cold weather areas though.

Sorry - not overblown at all.

Here is what I'll say .......... synthetics were made for a reason, and in the future - finding good ol dyno oil will be a thing of the past. Continue using what you wish - oil is so much better than it has been........

I don't see TOO many people using straight 30 weight in there 8N and then cutting that oil with a can of kerosene in the winter. BUT that was in the manual in 1948.

 

[ruger1980]

Synthetic is a marketing term. There is no industry standard regulating what a manufacturer may label as a "synthetic".

 

[fried1765]

Sorry - not overblown at all.

Here is what I'll say .......... synthetics were made for a reason, and in the future - finding good ol dyno oil will be a thing of the past. Continue using what you wish - oil is so much better than it has been........

I don't see TOO many people using straight 30 weight in there 8N and then cutting that oil with a can of kerosene in the winter. BUT that was in the manual in 1948.

My 1951 8n is still running strong.
It has never seen a drop of "synthetic" oil.
Being 81 years old, I suspect that I could even use regular mineral oil, and never live long enough to recognize any difference.

Changing oil regularly IS VERY IMPORTANT!
In my opinion, the FLAVOR of that oil is not nearly as important!

 

[TheOldHokie]

Synthetic is a marketing term. There is no industry standard regulating what a manufacturer may label as a "synthetic".

In Europe it has to be formulated using Group IV or V base oils. In the US it has to be formulated using Group III, IV or V base oils. You can thank Castrol and the US courts for the addition of Group III to that list.

Dan

 

[ruger1980]

There was no suit in court, it was a complaint raised to the NAD by Mobil. The NAD ruled that "synthetic" was a marketing term describing properties and did not define manufacturing processes. The majority of "synthetic" oils produced today, at least in North America are highly refined GroupIII base stocks. Many upper end GroupIII oils actually come close to GroupIV qualities as it is.
Or so my contacts at Mobil tell me.

 

[Mossy dell]

My Kubota manual gives the impression of strictly limited viscosities. Did some deep searching on Kubota's web site and those are recommendations, far from requirements. I posted elsewhere about it on this site, with a link.

I switched my new Kubota to 5w40 synthetic at 30 hours.

 

[FTG-05]

I can't remember the last time I bought regular dino oil.

 

[TheOldHokie]

There was no suit in court, it was a complaint raised to the NAD by Mobil. The NAD ruled that "synthetic" was a marketing term describing properties and did not define manufacturing processes. The majority of "synthetic" oils produced today, at least in North America are highly refined GroupIII base stocks. Many upper end GroupIII oils actually come close to GroupIV qualities as it is.
Or so my contacts at Mobil tell me.

Now we are niggling.

The decision handed down was the performance properties are what counts AND that synthetic connoted any high level of chemical manipulation as in the production methods being employed by Castrol. As a result very little of the synthetic oil on the shelves today are purely PAO or ester They are primarily highly refined Group III (dino) base oil blended with smaller amounts of Group IV (PAO) and V (esters).

The minimum viscosity index allowed for Group III oils is 120 so you don't get there without a lot of sophisticated chemical manipulation of the feed stock. .The naturally occurring hydrocarbons are chemically busted. ctalytically converted, and recombined to produce a very uniform and stable molecular structure (hydrocracking , hydrofinishing, isodewaxing, etc)

PAO starts with a single simple molecule (typically pure ethylene) and uses it as the building block for more complex hydrocarbons. The result is an even more uniform and stable molecular structure.

Both are considered synthetics. Group II oils are most definitely not and that is what you will find in anything labeled conventional or semi-synthetic.

Dan

 

[RalphVa]

I plan to put 0w30 M1 ESP in my new Kubota at 50 hour change. Right now, it's what I have in my JD 2025R. Still have 5w30 Castrol in the Isuzu diesel leftover from VW $. Will change to 0w30 M1 ESP next year for the 10 year change.

 

[jyoutz]

I think the difference is TOTALLY overblown (by the marketers of synthetic oil).
Synthetic likely does make a starting difference in cold weather areas though.

It’s more than just cold weather starting. I use synthetic in my Cummins . It not only starts better; it runs smoother in cold weather.

 

[fried1765]

It’s more than just cold weather starting. I use synthetic in my Cummins . It not only starts better; it runs smoother in cold weather.

Opinion!

 

[jyoutz]

Opinion!

My ears hear the difference. Consider that regular diesel oil is 15w-40 and synthetic oil is 5w-40. Of course it has better cold weather performance.

 

[TheOldHokie]

My ears hear the difference. Consider that regular diesel oil is 15w-40 and synthetic oil is 5w-40. Of course it has better cold weather performance.

What if the 15W40 is also synthetic? Its not really synthetic versus conventional as much as it is 5W vs 15W.

Dan

 

[RalphVa]

What if the 15W40 is also synthetic? Its not really synthetic versus conventional as much as it is 5W vs 15W.

Dan

Everyone should watch the video where they fashioned both a transparent valve cover and pan on an old car. Changed the oil on it to have fresh oil. Then started it at -23 C (-9 F). After SEVERAL minutes there was still no oil flow to the overhead valves. Here's the Youtube video:

. You run the time indicator over with your mouse to about 1/2 way because most of the first half is their description of how they did the valve cover and pan.

Our research people once did a test at -40 C/F with a transparent valve cover on a Dodge or Plymouth 024 type engine with various oils and filmed the valve cover. EVERY oil they tested smoked the valve cover except Mobil 1.

A few years later, we merged with Mobil. Problem solved.

The only true synthetics for vehicle usage is by Mobil or Pennzoil. Mobil makes theirs out of poly alpha olefin, which is a plastics feedstock and therefore makes it expensive. Pennzoil make theirs out of natural gas, a cheap feedstock. Think all the Group V ones are stuff like esters that Exxon have made for years for jet/turbine engines. Amsoil's feedstock is Group IIi, not synthetic. It's all hydrotreated crude oil.