B2601/B Series oil weight?

[Mossy dell]

Yesterday my dealer was delivering a bush hog and I asked parts to bring me a quart of oil. I'd noticed that my B2601 has used a bit in break in. "I think these come loaded with 10w-30," I said. I was told, "15-40 only for diesels!"

I know the owner's manual says either is okay. Messick's lists 10w-30 for this tractor. Two out of three Youtubers in their B2601 maintenance videos used 10w-30 and the other said his dealer supplied 15w40. I doubt the weight difference matters but am curious. I have always run synthetic oil after break in, from 30 weight to 50. Not sure why I used 50 in my JD970 but the synthetic stuff pours like water and I was working that tractor hard bush hogging.

What do you use and why? After break-in I'm leaning to Mobil Delvac 1 ESP Full Synthetic Heavy Duty Diesel Engine Oil in 5w-30 or 5w-40. They also have it in 0-40 (and maybe 0-30). I've done okay with Mobile One in cars and tractors and have read good things about this newer diesel oil. I do like the lower winter weight number because I've heard it's easier on engines at start up.

 

[Tire Biter]

5w 40 is ok. 15w 40 is what I use, Rotella T6 year round. It doesn’t get cold enough here for 5w40. I wouldn’t go any lighter IIWY in the summer.

 

[85Hokie]

MD - one thing to consider .......... synthetic oil after "breaking the engine in" is a purrrrrre myth........
Started about the time synthetics first came out ........ the ol line -
"gotta break it in FIRST then you can use synthetic..." is pure baloney.

The pouring like water IS one reason synthetics are "better" - but do not let the LACK of viscosity bother you at all - as the oil GETS to the operating temps - upwards of 200 F - is starts to behave like a thicker oil due to the modifiers in it , I know that is hard to wrap the ol' brain around - but that is what is it supposed to do - INCREASE in viscosity or rather protect the engine parts like a "thicker' oil.


If you could measure the wear on an engine - hell any engine - you will find that 95% of the wear occurs at the the turn of the key - that cold metal slapping the hell out of the other cold metal as the oil tries to get between those moving parts at startup. SO with the pour like water oils, it gets to the moving parts faster than the old stuff - and since it is getting there quicker - wear is lessened.

I use 5w-40 and 15w-40 Rotella T6 on all four of my Kubotas.

The real trick is using what the engine calls for - as the book does mention, all the above are ok to use.

And sometimes someone pours "gas engine" oil into a diesel - now is this an engine killer? No - but the thing about diesel oils, they do a much better job of containing all the "particulates" that burning diesels put out.

Synthetics are "better" for all the reasons you mentioned - but do not think that most new cars break in an engine then switch - they come straight from the manufacture with OEM synthetics.

Another myth - you cannot switch between them ..... again hogwash - as long as the oil is made for that particular engine - you can switch, hell mix em if you really wanted too.

Last thing - dirty oil is not a bad oil - actually it is a "good" thing - it means the oil is grabbing all those nasty little particulates of the burnt diesel.

 

[Mossy dell]

All good, Hokie. Great info. I said after break in but mean at the first oil change. That'll be this fall, probably well before 50 hrs. I hadn't thought of doing it now but do realize dino oil causes more wear meantime.

 

[Mossy dell]

An update for the record. May help someone else. My owner's manual seems very restrictive on oil, stating, "Proper SAE Engine Oil according to the ambient temperatures as shown above." Those temps “shown above,” from 14 degrees F to above 77 degrees F, call for SAE 30, 10w-30, or 15w-40. Below 14 F, 10w-30 is listed.

BUT, I found that Kubota has the latest information on line and seems to update those viscosities to recommendations, not requirements:

https://www.kubotausa.com/service-support/maintenance-schedules/lubricant-maintenance-schedule

 

[skeets]

Not a worry,, I run M1 sync 15W50 in the HD and M1 diesel 15W40 in both the BX and the B

 

[michigander]

I'm north east michigan
Mine came from dealer with 10w-30.
Ive been doing my annual changes with Kubota dino 10w-30

 

[number two]

I've been using Rotella 10W30 with perfectly satisfactory results.
Used oil analysis shows a TBN of 9 or better,with negligible moisture or acids,plenty of additive remaining.
I'm sure synthetic would be even better.
Good Luck!

 

[Fordtech86]

85hokie pretty much covers it. The main number to worry about is the last number (ie 5w-40) the 40 is what that oil will behave as at its operating temp. The first number is of some importance as well, thats how the oil will flow when cold. Many factors to this, but in general, good and clean oil will cling to surfaces and stay during downtime. The engine typically isn’t starting up dry, and full oil flow happens within seconds of engine start up. The manufacturer will recommend a conventional oil (10w30,15w40, etc) because either will be sufficient, remember they have to stand behind their recommendations. They won’t recommend/mention synthetic due to cost of ownership unless its truely important (sometimes the case in auto, not likely much an issue on tractor side).