Kubota only recommends 10w30 or 15w40

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I have a bx1880 that I’ve always put 15w40 in. I’m assuming it had 10w-30 as the factory fill. After the 50 hour service interval I put Kubota 15w40 in it. The owners manual only recommends 10w30 or 15w40 in it. Being a BitOGeR, I chose the thicker oiL for better wear protection. It has a coolant heater installed and it’s kept in a non heated garage so I figure I just run 15w40 year round and plug 🔌 her in when it’s below 32 degrees to get the coolant and oiL toasty.

There are some on orange tractor talk that claim that kubota diesel engines perform better with 10w-30 diesel oil but there’s something about how a tractor is used that I would think 15w40 would provide better wear protection.

Anyway

Can 5w-40 be ran in a Kubota? I know bota owners have run 5w40 in them before but I was wondering if 5w40 could be run as well? I don’t know what Kubotas aversion is to diesel oil other than 10w-30 or 15w40

My little bx1880 isn’t leaving my dads property anytime soon so I always have the option of plugging it in to warm it up before I crank it but I just wanted to know what Kubotas aversion 0w-40 or 5w-40 is?
 
The d722 engine will outlast the tractor by thousands of hours if you eventually repower it.

Your choice of any 10w30, 5w40, 15w40 HDEO is fine. I saw the debates on the forum as well, this (BITOG) is a more informed forum.
 
I would think either would be fine but would lean toward 10w30 if you are NOT maintaining significant acreage or running the tractor for long periods.

I run 10w30 Rotella or Delo in my Massey Ferguson 1643 compact (Tier IV, non turbo) and I run a 6' rotary mower, 2 bottom plow, box scrape, and other implements for hours at a time. Doesn't seem to be an issue... but I have never performed a UOA and change it at the factory interval of 150hrs.

Either weight should serve you well at the factory interval but if you are just doing loader work, yard duty stuff... then I would lean to 10w30. For what it is worth.
 
The d722 engine will outlast the tractor by thousands of hours if you eventually repower it.

Your choice of any 10w30, 5w40, 15w40 HDEO is fine. I saw the debates on the forum as well, this (BITOG) is a more informed forum.

Kubota terminology is 10w-30 or 15w40

They say “or 15w-40”

They have the temperature guidelines, which i assume are based on cold starts without a block heater.

I’m a firm believer that diesels should run in 15w-40 or 5w-40 in the winter, but that’s just me
 
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Tractors use
I would think either would be fine but would lean toward 10w30 if you are NOT maintaining significant acreage or running the tractor for long periods.

I run 10w30 Rotella or Delo in my Massey Ferguson 1643 compact (Tier IV, non turbo) and I run a 6' rotary mower, 2 bottom plow, box scrape, and other implements for hours at a time. Doesn't seem to be an issue... but I have never performed a UOA and change it at the factory interval of 150hrs.

Either weight should serve you well at the factory interval but if you are just doing loader work, yard duty stuff... then I would lean to 10w30. For what it is worth.

Serious question, why do you prefer 10w-30 over 15w-40 for tractor work? Kubotas go to oil is 10w30 whilst John deere and yanmar me go to HDEO is 15w-40, temperature depending.

And speaking of John deere, what’s sad about John deere dealers is that every man working at a John deere dealership would own a Kubota in a heartbeat lololol
 
I ran my kubota B7500 on 5w40 for 12 years because I was using it all year long, now that it is only doing summer work I moved to 15w40. Even though it is water cooled the radiator and front screen can really get clogged with grass clippings on windy or really dry days. I keep a close eye on the temp gauge and stop and clean the screen and radiator every 90 min or so, I feel better with a bit thicker oil (Rotella T6 15w40). Its now 21 years old and I cant afford to buy another one.
 
And speaking of John deere, what’s sad about John deere dealers is that every man working at a John deere dealership would own a Kubota in a heartbeat lololol

I dont tend to ask people at John Deere or Kubota dealers anything except for parts when I need them and cant get them cheaper online. Their opinions are pointless ford/chevy mudslinging. I own and operate both and they have their plusses and minuses.
 
Tractors use


Serious question, why do you prefer 10w-30 over 15w-40 for tractor work? Kubotas go to oil is 10w30 whilst John deere and yanmar me go to HDEO is 15w-40, temperature depending.

And speaking of John deere, what’s sad about John deere dealers is that every man working at a John deere dealership would own a Kubota in a heartbeat lololol

Primarily because my ambient temps are typically 70- 90 during summer.

I also use the tractor in winter for snow plowing.

Basically, I dont want to change oil for just the winter months.

So, I place more importance on the lighter weight of 10w30.
 
And speaking of John deere, what’s sad about John deere dealers is that every man working at a John deere dealership would own a Kubota in a heartbeat lololol
I asked that question to a diesel equipment mechanic I know. He told me that in his opinion, the older Deere stuff was better, but in the last 20 years that has changed. Kubota while proud of their parts, are not prone to such failure as the Deere. While parts on The Deere are cheaper, they are more just that, cheaper. He says he works on 5 to 1 Deere and Kubota. Interesting stat, being as there are many many more Kubota tractors and compact stuff out there than anyone else.

Funny thing about it. He told me the number one issue, beyond mice infestation and damage, was the cooling system. Not because of design, but because no one ever changes the coolant, that and overheating due to radiator clogging.
 
I ran my kubota B7500 on 5w40 for 12 years because I was using it all year long, now that it is only doing summer work I moved to 15w40. Even though it is water cooled the radiator and front screen can really get clogged with grass clippings on windy or really dry days. I keep a close eye on the temp gauge and stop and clean the screen and radiator every 90 min or so, I feel better with a bit thicker oil (Rotella T6 15w40). Its now 21 years old and I cant afford to buy another one.
I've been running my B7500 on 5w-40 for years as well. And yes that radiator sure does seem to clog pretty easily. Maybe its just the type of grass I have or the type of work I use it for, but I have to unclog it fairly frequently and the effect that has on the temperature gauge is readily noticeable. I usually use my leaf blower and the amount of dust and grass and bugs and junk that go flying out of there after just an hour or two sometimes is quite surprising.
 
I asked that question to a diesel equipment mechanic I know. He told me that in his opinion, the older Deere stuff was better, but in the last 20 years that has changed. Kubota while proud of their parts, are not prone to such failure as the Deere. While parts on The Deere are cheaper, they are more just that, cheaper. He says he works on 5 to 1 Deere and Kubota. Interesting stat, being as there are many many more Kubota tractors and compact stuff out there than anyone else.

Funny thing about it. He told me the number one issue, beyond mice infestation and damage, was the cooling system. Not because of design, but because no one ever changes the coolant, that and overheating due to radiator clogging.

Ive found out when mowing that every hour or two the radiator screen AND the radiator need to be cleaned, I use an air compressor on both.
 
I asked that question to a diesel equipment mechanic I know. He told me that in his opinion, the older Deere stuff was better, but in the last 20 years that has changed. Kubota while proud of their parts, are not prone to such failure as the Deere. While parts on The Deere are cheaper, they are more just that, cheaper. He says he works on 5 to 1 Deere and Kubota. Interesting stat, being as there are many many more Kubota tractors and compact stuff out there than anyone else.

Funny thing about it. He told me the number one issue, beyond mice infestation and damage, was the cooling system. Not because of design, but because no one ever changes the coolant, that and overheating due to radiator clogging.
Where do you source your info for many more kubota?
Here its probably 10-1 deere to kubota.

They both have good stuff.. IMO. Although alot of deeres at least the older have bmw plus levels of engineering..
remove motor to change the starter type stuff.
 
He says he works on 5 to 1 Deere and Kubota. Interesting stat, being as there are many

Where do you source your info for many more kubota?
Read the excerpt above from my statement. 40 years of working on farm and construction equipment is worth more than any "source" you can find online.

The Kubota vs Deere argument has no objective value anywhere. In construction, Kubota is king, for all compact machines.

My source for that is 25 years in the construction industry in the southeast and south west, with many trips north for remote jobs.

But Kubota does not make the same things as Deere on the larger end, industrial 300hp combines and the like,so there is no comparison as Kubota does not make one.
 
Recently, I went to the local kubota dealer for some filters.

The dealer told me that in cold climates, 15w40 was needed, and in hot climates, 10w30 is needed. Of course he stated this with authority, and funny enough, i have the manual on my phone for my kx91.......which of course proved him wrong, 180 degrees wrong.

Be careful with these parts guys. There is no difference in a kubota 25hp engine from 20 years ago.

There are likely trillions of hours on 15w40 dino oil in kubotas around the world.
 
on 100 hp and above for sure....Kubota is a small equipment company.

The smaller below 50 hp market is Kubota.....i suppose it depends on you view, from what you see in industry.
 
Kubota terminology is 10w-30 or 15w40

They say “or 15w-40”

They have the temperature guidelines, which i assume are based on cold starts without a block heater.

I’m a firm believer that diesels should run in 15w-40 or 5w-40 in the winter, but that’s just me


Ford
And Dodge tricks with diesel would disagree 🙊🙊🙊
 
Kubota terminology is 10w-30 or 15w40

They say “or 15w-40”

They have the temperature guidelines, which i assume are based on cold starts without a block heater.

I’m a firm believer that diesels should run in 15w-40 or 5w-40 in the winter, but that’s just me
I agree 5w40 year round never ever problems and best in my opinion from -20F to 100F you are covered never this screwing around with seasonal changes.
 
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