Synthetic or Conventional motor oil in Kubota diesels

top gnome

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Equipment
b2301 w bh fel grapple back blade snow plow forks
Dec 12, 2021
458
213
43
Fundy shore nova scotia
After their break-in period, I switched to Rotella T6/5w-40 full syn in both my BX's and my son's BX. Now it seems very hard to get in my area. I stopped by my local AA store for another item, and they had 1 gal of it at $36. bucks. No more available. I purchased it. Home Depot used to have it for $22. bucks. It seems the other Rotella T oils are available in my area. T6 nowhere to be found. I do see it on Amazon, at + $50. a gal. Not sure what the issue is with the T6. Must be that it is full Syn.
thank you all for the answers. I bought 2 jugs so that would be 3 oil changes. Walmart had it. There website showed none in stock but when I went to the store they had a bunch. My plan is to change to synthetic at 50 hours. We do not get very hot weather.
 

jyoutz

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Equipment
MX6000 HST open station, FEL, 6’ cutter, forks, 8’ rear blade, 7’ cultivator
Jan 14, 2019
2,458
1,565
113
Edgewood, New Mexico
What does your owner's manual say? That's what you need to use.
The owners manual just gives the required oil viscosity and CJ-4 rating. You can buy both conventional and synthetic that meet those standards, so the owners manual is basically silent on this topic.
 
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jyoutz

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MX6000 HST open station, FEL, 6’ cutter, forks, 8’ rear blade, 7’ cultivator
Jan 14, 2019
2,458
1,565
113
Edgewood, New Mexico
Absolutely none available in our area here in NW IL and southern WI. Hell ANY synthetic diesel engine oil is near impossible to find though at the local "farm" stores they do sell a store brand that is occasionally available. Oddly a few months ago our local Menards store was running a sale on Rotella T-6 5W-40 nearly giving it away. IIRC it was $15 gal. I never dreamt it would become so scarce. I bought 2 gallons to complement one I had on hand (though I did use that one) so I have 2 left. So I currently have enough for 2 oil changes. I am hoping Shell gets it act together before I actually "need" it :D
Go to your local diesel truck shops, not farm supply stores. They seem to have diesel oil in stock.
 

Vlach7

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L47 305DT JD500C
Dec 16, 2021
258
167
43
Frazier Park Ca
Whatever you use, change it on schedule, had an 86 Maxima, changed the oil every 5000 with Walmart base generic and used the cheapest gas, usually Arco here in Southern Cali. After 30 years I drove it to the auto salvage yard with over 505,000 miles, not kilometers, same motor, no rebuild, same manual trans. Regular maintenance, fix things when they need to be.
 
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Whatscooking

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Equipment
Grand L 3130. BX2360. RTV900. GRASSHOPPER 721D
May 19, 2021
122
60
28
Indiana
Synthetic oil has a habit of seeping out if the the engine is not designed for it,seals aren't compadable.
Ive been remimded several times now that my reply isn't correct. What i ment to say but it came out wrong, if you put synthetic in something that is leaking out the regular dino oil already it will really leak even more with the synthetic.
My former life as a fleet mechanic with older trucks to maintain was basic 80/90 in the trans and the diffs. Along came the newer trucks calling for a certin type of synthetic oil for the Spicer 5 speeds, the diffs called for a different type of synthetic? Found out the older and worn 465 and 435 4 speeds in the older trucks leaked so bad i had to keep 80/90 aroundfor them.
Synthetic oils require good seals.
 
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ACDII

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Equipment
B2410, L352 Loader, Woods BH70-X backhoe
Oct 21, 2021
660
407
63
Illinois
I have to change the oil in my F350. Thats only 4 gallons of the stuff. Last time I used Rotella T5 full synthetic, it was about $80 in oil and filter to do it myself. I also have to change the oil in my F150 and that one MUST be synthetic or at least Semi Synthetic. I am considering going with Royal Purple as I found some good information on it that is beneficial for that crazy cam timing stuff on the Ecoboost.

I use Mobil 1 in the B2410, it meets the standards called for from 2001. I have to see what the quantities are for the L4060 and make sure I buy enough b=for both the truck and the tractor.

I am going to first take a sample of oil from the truck and have it analyzed first to see if I can extend it since I barely put 3K on it the past year before I decide to change it. Since it is full synthetic, and none of the trips are cold start stops, they always allow for a full operating temp for engine and trans, any moisture would be burnt off, it should still have plenty of life left. If it were conventional or semi syn, I would just change it and be done, but I went to full synth for this very reason.
 

lynnmor

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Equipment
B2601-1
May 3, 2021
1,293
998
113
Red Lion
I have to change the oil in my F350. Thats only 4 gallons of the stuff. Last time I used Rotella T5 full synthetic
Rotella T6 is full synthetic, T5 is a blend. Ford has an approved list of motor oils for the 6.7 diesel, most likely they have it for others, I would search for that list before buying into advertising. I use 13 quarts of Rotella T6 in my 6.7 diesel, be sure that the quantity is correct, Ford printed some owners manuals and had dealer software that was incorrect.
 

ACDII

Well-known member

Equipment
B2410, L352 Loader, Woods BH70-X backhoe
Oct 21, 2021
660
407
63
Illinois
AH, I had to look closer at the label, it was sun faded from sitting outside, all I saw was synthetic, missed the blend part. Either case, still going to sample before changing it. the last change was the dealer fill, no clue what oil was put in, but the lab results were promising.
 

JerryMT

Active member

Equipment
Kubota M4500, NH TD95D,Ford 4610
Jun 17, 2017
528
156
43
The Palouse - North Idaho
The owners manual just gives the required oil viscosity and CJ-4 rating. You can buy both conventional and synthetic that meet those standards, so the owners manual is basically silent on this topic.
Whatever the manual recommends in terms of SAE grade and API classification is what you should use. For example ".....SAE 15W40 API classifciation CJ-4...."
Remember that as far as API classification they are backward compatible so they can be used in older machinery like something requiring API CH-4 classification oil.

As far as the SAE grade, the base viscosity index oil for a machine is always denoted by the last numbers. In the case of 15W40, "40" is the base oil viscosity that the engine lube system is designed for. That's what you must use if the owner's manual calls for it. It is the "hot oil" viscosity index. The first number, which is the "cold oil" viscosity index, can be chosen for "cold" operating performance. In the summer you can chose 5, 10 or 15. You might also chose 0.
In the winter, to improve starting in cold temperatures, you might limit the cold viscosity index number to 5 or 10, or even zero. There's nothing wrong with using 0, 5, and, 10 designator year around as long as you owner's manual does not prohibit it. However you must use the "40" designator year around.

Thems the basics. Now finding 10W40, et al diesel grade oil is another matter.

I hope this helps you.

(Ref: 540 RAT - Tech Facts, NOT Myths (wordpress.com) )
 

jyoutz

Well-known member

Equipment
MX6000 HST open station, FEL, 6’ cutter, forks, 8’ rear blade, 7’ cultivator
Jan 14, 2019
2,458
1,565
113
Edgewood, New Mexico
Whatever the manual recommends in terms of SAE grade and API classification is what you should use. For example ".....SAE 15W40 API classifciation CJ-4...."
Remember that as far as API classification they are backward compatible so they can be used in older machinery like something requiring API CH-4 classification oil.

As far as the SAE grade, the base viscosity index oil for a machine is always denoted by the last numbers. In the case of 15W40, "40" is the base oil viscosity that the engine lube system is designed for. That's what you must use if the owner's manual calls for it. It is the "hot oil" viscosity index. The first number, which is the "cold oil" viscosity index, can be chosen for "cold" operating performance. In the summer you can chose 5, 10 or 15. You might also chose 0.
In the winter, to improve starting in cold temperatures, you might limit the cold viscosity index number to 5 or 10, or even zero. There's nothing wrong with using 0, 5, and, 10 designator year around as long as you owner's manual does not prohibit it. However you must use the "40" designator year around.

Thems the basics. Now finding 10W40, et al diesel grade oil is another matter.

I hope this helps you.

(Ref: 540 RAT - Tech Facts, NOT Myths (wordpress.com) )
I agree with your comments regarding viscosity and API classification. But the specifications can be met with either conventional or synthetic oil. That is my point: the manual is silent on this.
 

JerryMT

Active member

Equipment
Kubota M4500, NH TD95D,Ford 4610
Jun 17, 2017
528
156
43
The Palouse - North Idaho
I agree with your comments regarding viscosity and API classification. But the specifications can be met with either conventional or synthetic oil. That is my point: the manual is silent on this.
By implication, synthetic, conventional, or synthetic/conventional blends can be used at the owner's discretion since they are not expressly prohibited.
 

jyoutz

Well-known member

Equipment
MX6000 HST open station, FEL, 6’ cutter, forks, 8’ rear blade, 7’ cultivator
Jan 14, 2019
2,458
1,565
113
Edgewood, New Mexico
By implication, synthetic, conventional, or synthetic/conventional blends can be used at the owner's discretion since they are not expressly prohibited.
Yeah, that’s what Kubota support basically said when I contacted them. My point is the owners manual isn’t clear on this. And that question is the focus of this thread.
 

JerryMT

Active member

Equipment
Kubota M4500, NH TD95D,Ford 4610
Jun 17, 2017
528
156
43
The Palouse - North Idaho
Yeah, that’s what Kubota support basically said when I contacted them. My point is the owners manual isn’t clear on this. And that question is the focus of this thread.
I have come across these type of threads in many different forums and my personal opinion is that this problem is "over thought".

The owner's manual provides the basic info on the manuafacturer's requirements and they are supposedly based on the design of their engine and it lubrication system. The legal beagle's get into the act so they only want to say enough to cover the manufacturer's butt. Long time equipment users (farmer's, ranchers, etc) don't have a problem with these but the industry has seen a growth in sales SCUT's and CUTS and people who buy them want to do "everything right" for their new piece of machinery. It almost becomes an obsession and these folks think that if they put a drop less of oil in the machine then specified, the tractor will self distruct. So they want to know every possible option for lube oil. And they want the "best oil" for their machine.

There in comes the rub. How do you define the "best oil". The best oil is not specified by brand. It is specified by requirements of the folks that designed and build the engine it is based on the SAE Grade and the API service Classification. The only place that I have seen test data on engine oil Performance , (and even that data used measured wear as the criteria for determing the "best oil". ) was in the reference I provided in a previous post.

I keep promising myself that I won't get drawn into these endless circular discussions on lube oil performance and I repeated fall into the trap. 'Nuff said.
 
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