Hello Kubota man, I understand that you didn't ask about a particular brand of oil. That's why my first line said that a diesel rated oil has additives that help to prolong engine life in a diesel engine. Diesel oils are formulated to help capture contaminents and keep them away from critical internal parts. Even though some or maybe even most gas oils will meet Kubota specs a diesel oil will have additives that are designed just for the higher demands of a hard working diesel engine no matter the size. I'm looking at a 1991 Kubota maintenance chart for M7580-M8580-M9580 which lists using engine oil with a API rating of CC or CD. Now looking in my 2004 manual for my M 9000 it says use engine oil with a API rating of CD, CE or CF. In the special notes section it says this. When using low sulfer fuel or high sulfer fuel Kubota recommends API CF, TBN>10. A API oil with a CD rating is no longer listed on the chart. This leads me to believe that engine oil requirements have changed from 91 to 04.
Side note, "Kubota recommends Super UDT for optimum protection and performance".
You answered, "not at all" to the question of "any old oil will do". You want your BX to last forever and have a happy life. You also stated that you live in a cold climate and you have a four season tractor. I hope your BX will last you a life time and I want the same thing for my tractors. The question was then thrown out to your orange feathered friends of what type and weight oil do you need. Just like the Ford and Chevy debate I have your back. I'm in no way trying to sell you on any brand of oil. I'm simply passing along information that I have gathered from years of trouble free service.
Type: Heavy Duty diesel - weight: 5w30 API CI-4+, CF TBN 12.1 pour point: -58F
All I'm doing is trying to give you some facts on a product that has proven to me that it works and does what it's designed to do. I do believe in Amsoil because I have been using it for over 15 years. I don't know anything about amyway school. I would like to understand how a person that has never used Amsoil can have a real opinion about how it work. Maybe when everybody gets out of the shower and off the beach they can take the time to show me one post where I have tried to make a sale. Don't believe me, fine. Think I'm completely full of it, fine. It would be nice to get some comments that are based on facts instead of personal preference. I don't know you guys any better than you know me but we all love our Kubotas. I have nothing to gain by telling a lie and would never pass along false information. OTT is all about helping each other not hurting. I share my own experience with a product that I have to purchase for my use. It makes no difference to me if you choose to use Amsoil or not. I have nothing to gain either way.
Go to the Shell Rotella home page and find their QA section and then read what Shell has to say about the benifits from using synthetic oil. This info is not from Amsoil or myself.
RDR, have you ever used Amsoil?
If not then your negative opinion of Amsoil products is based on what?
I think a hot round of double doubles and a box of apples fritters from Timmies are just awfull. Burger King is much better. I guess BK is okay. My brutal assalt on Timmies has no real facts. I never even heard of Timmies before the bet between SDV and Mr K. I don't know how a double double taste or what a box of apple fritters even looks like. My (EXAMPLE ONLY) opinion of Timmies is based on nothing. Never tried it so how can I even give any type of opinion on there food? A man born blind has no way of knowing the difference between daylight and dark.