Synthetic or Conventional motor oil in Kubota diesels

[hedgerow]

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.

 

[mcfarmall]

I use Rotella dinosaur oil.

 

[RCW]

hedgerow - - common question.

In the old days, "they" said you needed X hours or miles before switching to synthetic so rings would set. My Harley-Davidson was a good example.

Now-a-days, folks say not necessary to wait before switching.

I did wait 2 changes before switching my little BX, but the difference between 15w-40 and 5w-40 Rotella T6 synthetic was great for cold winter starts.

 

[BruceP]

...the difference between 15w-40 and 5w-40 Rotella T6 synthetic was great for cold winter starts.

I second that one!! Use 5w-40 Rotella T6 synthetic in everything I can. It is perhaps the BEST motor-oil on the shelves at WallyMart.

 

[lmichael]

No engine I own touches plain old dino juice anymore. I have been using synthetics since Mobil came out with the very first M1 product way back in the early 70's in the round metal can. Back than it was a 5w20 only. I used it in my 69 Caddy with 472 high compression big block, I used it in my BMW motorcycle (flat twin) R60/6, I used it in my BMW 2002, and the list of engines and vehicles goes on and on. My buddy used it in everything he's owned as well. From the same time period. Never once an issue of ANY kind. Today in my small engines Shell Rotella T-6 is the ONLY oil they get. Before my Kubota G2160 it went in my Honda 4514 (2 cyl water cooled), my Simplicity Sovereign with big Kohler Vtwin before than and before than my old Allis Chalmers B series with Briggs air cooled 16 hp single. Use it in my walk behind Honda as well and in my Honda snowblower as well. Mobil 1 0w20 is all my car gets (except for my new RAV4 Hybrid uses M1 0-16. In this day and age there is no valid reason to use dino juice unless you have a mosquito fogger. IOW something you fill with oil and check the gas. Bottom line I neevr touch anything but high quality synthetics. They protect better, clean better and flow better

 

[Jim L.]

Unless the engine gets a lot of hours put on it, probably more important is to change the engine oil at least once a year.

My generators need an easier start in cold weather so then I switch to a synthetic for easier cold start.

But my tractor is not an everyday, 10 hours a day machine. So I am fine with conventional oil changed yearly.

 

[85Hokie]

I love this topic..........

If we could all just understand the slippery stuff a little better - knowledge goes a hellava long way, of course once it is understood completely!

All those tails of synthetics doing this and that to engines - pure horsesht ...........

hey, did you see the story of bigfoot living in Miami? Of course you didn't I made the story up......... just like the problems of using synthetic oil day one in an engine.

In the near future - good old dyno oil will be a thing of the past - simply because synthetics do it all much better and longer

You still use filament bulbs in the table lamps? Or have you switched to LEDs?

 

[DDCD]

My 60 year old tractor gets 15-40 rotella dino. It has the factory leak/replenish feature of old tractors so it's always getting an oil change.

I'm not sure what I'll do to the 2501. Mobil1 5 40 seems to be a favorite, but the manual does not mention it, only 15 40 or 10 30.

Rotella T4 15-40 dino at $30 for 2.5 gallons is about as cheap as it can be.

I'll probably use synthetic at 50 hours since the tractor is brand new.

 

[mcmxi]

I run the same fully synthetic 5W-40 oil in my '02 Ford F250 7.3L Super Duty and the MX. It's made by Schaeffer and I buy it through Amazon. One 6 gallon case has enough oil to change out both with a little to spare (about a quart) to top off if I need to.

9000-006 SynShield OTR Plus Full Synthetic 5W-40 (schaefferoil.com)

I run Mobil 1 10W-30 synthetic in my Jeep that I've had for more than 20 years and have done so for most if not all of those 20 years.

 

[DaveFromMi]

Are synthetics compatible with the DPF?

 

[Whatscooking]

Synthetic oil has a habit of seeping out if the the engine is not designed for it,seals aren't compadable.

 

[TheOldHokie]

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.

Perhaps your question needs to be refined (pun intended) a bit.

Most synthetics on the shelf today are formulated using Group III+ base stocks which are simply very highly refined crude (e.g. dino) oil. Their performance is nearly as good as Group IV (PAO) base stocks.

So go back and ask those dealers if you should be using a Group III or Group IV based oil and see what they have to say.

Then armed with that information go shopping and see if you can tell which base oils are used and in what proportions in say Mobil 1 10W30. That is a CF approved diesel oil which is all Kubota says you need to worry about

Dan

 

[85Hokie]

Synthetic oil has a habit of seeping out if the the engine is not designed for it,seals aren't compadable.

" early synthetic motor oils were ester-based and some engine seals are ester-based, "

The formulation has changed a bit over time too - " Those outdated synthetic oil formulations did, in fact, cause excessive degradation of the seals, which led to oil leaks."

“If there is a passageway or seal that oil is leaking through, the difference in viscosity at operating temperature is too small to affect whether or not oil can slip by. The leak is going to continue to leak. The problem is that you have a failed seal, not that the oil is the wrong viscosity.”

https://www.enginelabs.com/news/synthetic-motor-oil-and-older-engines-old-wives-tales-debunked/

 

[Whatscooking]

I have a BMW GS motorcycle, put synthetic in the final drive then started seeing oil seeping out the front seal. Have went back to dino oil and the seep has eventually stopped.
Only put in what the manual says for me now.

 

[TheOldHokie]

I have a BMW GS motorcycle, put synthetic in the final drive then started seeing oil seeping out the front seal. Have went back to dino oil and the seep has eventually stopped.
Only put in what the manual says for me now.

BMW is very much committed to the use of synthetic oils in all of their products. They currently specify:

BMW C-SAF-XO SAE 75W90

for use in the final drives of ALL motorcycles built after 1970. It is a synthetic oil. Perhaps you have a seal that needs to be replaced....

Dan

 

[mcmxi]

Are synthetics compatible with the DPF?

This is an interesting question. Ultimately, it would come down to whether synthetic oils increase the rate of ash accumulation in the DPF compared to conventional oils. You can bet that manufacturers of diesel rated oils are very serious about reducing ash build up in the DPF system since that would have a direct impact on sales. I can only image the emissions related costs to companies running fleets of diesel equipment.

Anything we can do to extend the regen intervals is a good thing since that correlates to ash build up which will eventually end the life of the filter. Kubota specifically tells us not to idle the engine for extended periods since it produces more unburned particulates in the exhaust which will produce more ash in the DPF. If it were a simple case of comparing the cost of replacing the DPF after X number of hours or rebuilding the engine after X number of hours we might opt for the former and choose to putt around at low rpm. However, we don't have those numbers for comparison and don't know if low rpm and DPF ash accumulation lead to engine damage. Kuboto seems to think it might with all of their regen warnings. Running the engine at high rpm and running it hot in combination with cold starts leads me to think that a good synthetic oil is the best way to proceed.

My MX has almost 60 hours on it and I've had one regen at around the 30 hour mark. I did the 50 hour service at 49.6 hours and added Schaeffer oil. I haven't had another regen yet but I've been doing a lot of mowing in the 2,200 to 2,400 rpm range so it might extend the regen interval. Will the oil help in this regard? I'll most likely never know.

 

[hagrid]

BMW is very much committed to the use of synthetic oils in all of their products.

They are also very committed to performing radical cashectomies upon my wallet for scheduled maintenance tasks.

 

[JerryMT]

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.

Opinions are like belly buttons....everybody's got one!

Unless there are hard facts to the contrary, use what the owners manual says to use with regard to SAE weight and API classification. That what the engine or system component ( tranny's, rear axles, etc) was designed to run with.

If there were hard facts to the contrary, then the equipment manufacturers would change the design and lube recommendations. My Subaru Outback recommends 0W20 full synthetic mainly for mileage reasons because it says you can use something else ( I can't remember what) in a pinch but it will affect the fuel mileage.

Forums like this are full of discussions like this. Most oils are backwards compatible so the old engines can use the new oils and they should. Arguing about whether synthetic oil is better than dino oils without hard data boils down to giving opinions. So as a minimum, use what the owners manual recommends in SAE and API classification or it's modern counterpart.

 

[mcmxi]

Opinions are like belly buttons....everybody's got one!

If there were hard facts to the contrary, then the equipment manufacturers would change the design and lube recommendations.

Arguing about whether synthetic oil is better than dino oils without hard data boils down to giving opinions. .

I have no dog in this race since it makes no difference to me what others use but there's plenty of data to support the "opinion" that synthetic oil is superior to conventional oil. Whether or not our Kubotas benefit from using synthetic oil or whether synthetic oil is cost effective for most of us is absolutely opinion and not data just as your comment about manufactures changing lube recommendations is purely opinion. The idea that manufacturers do what's best for the customer is ridiculous ... another opinion.

 

[ManBitesDog]

15w-40 Dino Oil is, today, pretty darn good oil.

However, 5w-40 Synthetic is just simply better at everything. Everything.

It starts moving faster, so it gets to vital engine parts sooner. It will allow your engine to run cooler, it gets up to operating temperature faster, it lasts longer, it resists viscosity break-down due to high heat better, it will give you better fuel economy..... Everything about it is better if you have a good engine.

If your engine is a leaker, it gets old spending the bucks for Syn. If it rattles and is on its last legs...... Just use whatever.

But for a new engine? Syn is the only way to go, IMHO. But 15w-40 isn't a bad oil unless you're operating anywhere near 0 degrees F. Especially on some of the newer engines that like to go into regen unexpectedly.