Understanding oil requirment for Kubota engines

[sixdogs]

I'm confused and this has probably been beaten to death but I am not sure which rating engine oil to use in my Kubotas.

Kubota oil in the jug is rated CJ4, Ci4 plus, Ci4,CH4,CF4,CF,CE,CD,CC/SL, SJ. So is Rotella, etc.

Kubota service bulletin says that non-EGR engines can use CF, CF4,CG4, CH4, Ci4

So, can I use CJ4 oil in engines that show a lower requirement? Use a CJ4 rating in an engine that requires Ci4? Now, I know conventional wisdom says you can use an oil rated correctly or an oil rated higher than required. I know that. But I also know that the reduction in phosphorus and ZDDP in the higher rated oils has cause some gasoline engines to suffer premature camshaft wear and I don't want that to happen. Is this true with Kubota diesels? Sometimes I work mine pretty hard and don't want problems I can avoid.

Does anyone know more on this or can enlighten me? Any advice appreciated.

 

[number two]

You can most surely use CJ4 oils with no worries in your tractor!
Kubota manuals are woefully out of date on oil specifications.
The factory fill on Kubota tractors is 10W30 conventional oil.
The specs on the jug are correct.
Good Luck!

 

[oosik]

The service manual for my 2009 M6040 recommends either 10W-30 or 15W-40. As far as the "modifiers" - for low sulphur fuel they recommend CF, CF-4 or CG-4 which as #2 indicates is WAY out of date. The oil I use is CJ-4plus, CJ-4, CI-4, CH-4, CF-4, CF, CE, CD, CC/SL,SJ.

Looks like it can be used for just about everything including deep frying chicken.

 

[motownbrowne]

As long as the CJ oil is also backwards compatible, which all of the ones I've seen are, you're good to go. My manual actually says not to use a cj oil, but as far as I can discern, they mean one that is only cj rated and not backwards compatible.

I called my dealership on this issue, because the Delo 400le that I wanted to run is cj rated. The guy says, "well just come and buy the Kubota brand oil that we sell, and you'll know it's the right stuff". So I asked him to go get a bottle and read me the ratings. They were the same as the Delo 400, so I used what I had.

 

[sixdogs]

Kubota really needs to clarify this issue so guys with 15 year old Kubotas will know if using modern rated oils with lower ZDDP amounts will hurt their engines. They need to say yes or no. In fact, until a couple years ago they did not allow the use of 15W40.

I do know that in many gasoline engines with flat tappets (lifters), modern oils rated higher than that called for will indeed hurt the engine. Kubotas, at least the older ones have flat tappets. I also know modern oils have reduced ZDDP levels that can hurt an engine with flat tappets. So, does modern oil hurt an older Kubota, yes or no?

 

[number two]

Simple answer is no,modern oil will not hurt your older tractor!

Current gasoline oil spec is SN.that's the stuff really low on ZDDP,
The modern gasoline engines use low friction valve train components,and the ZDDP is harmful to oxygen sensors and catalytic converters.
Car builders are happy to see the zinc go so their emmision components will last thru the warranty period.

Diesel CJ4 oils have a gas rating of SM or lower.
More ZDDP and moly is also being added for anti-wear to replace zinc.

Please feel good about CJ4 oil in your tractor!
Also not wanting to start an oil discussion war.

Good Luck!

 

[sixdogs]

Simple answer is no,modern oil will not hurt your older tractor!

Current gasoline oil spec is SN.that's the stuff really low on ZDDP,
The modern gasoline engines use low friction valve train components,and the ZDDP is harmful to oxygen sensors and catalytic converters.
Car builders are happy to see the zinc go so their emmision components will last thru the warranty period.

Diesel CJ4 oils have a gas rating of SM or lower.
More ZDDP and moly is also being added for anti-wear to replace zinc.

Please feel good about CJ4 oil in your tractor!
Also not wanting to start an oil discussion war.

Good Luck!

That sure looks like the answer. Thank you.