Why "Diesel" oil?

[RanchMan]

Re: Why \"Diesel\" oil?

Richard-

Hate to admit it, but I've been pretty confused running the "Oil Gauntlet" myself (Does that sound strange for a Texan? /w3tcompact/icons/grin.gif)

Anyway, found this document. Helped me a lot as to understanding what the grades are, what replaces what, etc. Hope it helps....

<A target="_blank" HREF=http://www.api.org/programs_services/quality/oilguide.pdf>http://www.api.org/programs_services/quality/oilguide.pdf</A>

 

[njrqs]

Re: Why

Just looked. Mine is an API CG 4. Maybe our letters mean different things to yours.

Sure enough, lists all the diesel and turbo diesel applications, as well as the petrol and LP gas engines it is for.

I think it is mainly a diesel oil that can be used in a petrol engine.

Hmmmm

 

[TresCrows]

Re: Why \"Diesel\" oil?

Mobil specifically states that Mobil 1 which is SL/CF is suitable for all light diesel engines that required CD spec oil. That means according to my Kubota manual that recommends a CD oil then that Mobil 1 is a suitable oil for my Kubota. A call to Mobil confired this. It is also clearly stated in their brochure on Mobil 1 oils. A small compact tractor is a light diesel, a 500 horsepower or more CAT turbo-diesel installed in triplicate in an offshore oil field service crew boat would not be, for example. J

 

[djradz]

Re: Why

In Michigan, 15W-30 or 40 is too heavy for my diesel NH TC-40D in the winter. I seems to take quite a few seconds for the oil light to go off due to the long path oil must travel from the lower portion of the engine up to the head. Therefore, I generally use a 10W-30 or even 5W-30 during the winter. Only synthetics or semi-synthetics carry the CD rating at these weights. NH ships all their tractors with 10W-30, even for summer use, so I'm thinking they too must feel 15W-30 is a little to heavy for all around use, although if I lived down south, I'm sure that's the way I'd go.

 

[MChalkley]

Re: Why \"Diesel\" oil?

Richard - I expect the answers you've gotten already answer your question sufficiently. For a "real-world" anecdote, you might want to check out <A target="_blank" HREF=http://www.tractorbynet.com/cgi-bin/compact/showflat.pl?Cat=&Board=custom&Number=77301&page=0&view=collapsed&sb=5&o=7&fpart=7&vc=1>this page</A>, about 2/3 the way down. Synopsis: I put Castrol GTX in my EarthForce EF-500 w/Kubota 56hp turbo-charged engine. John Miller III caught my gaff and informed me that GTX isn't diesel-rated (it used to be, and I live in the past a lot). Anyway, in researching whether I needed to change it immediately, I made some phone calls. The end result was that even Castrol said "We would recommend that you change the oil immediately.... GTX is no longer diesel rated and should NOT be used for a diesel application." A complete quote of the most pertinent post follows:

<font color=blue>I asked Castol's tech support dept about my goof, and here's the reply I got: "We would recommend that you change the oil immediately.... GTX is no longer diesel rated and should NOT be used for a diesel application." Note the words "is no longer". I think I now realize how I made this mistake. It used to be rated for diesel service. Not having purchased petroleum products in quite a while, I just didn't look closely enough at the ratings, I guess, though I sure thought I did. I know I saw the CG-4 rating on something I looked at, but it sure wasn't the Castrol GTX. Again, thanks for catching that one for me, and potentially saving my engine!

I also called the Amsoil tech services department and asked them about non-C-rated oil in the Kubota turbo-diesel, and he had two words: "Drain it." I was hoping the rating had to do more with longevity issues. Alas - I'm afraid not. At least I only ran the engine a couple hours on it...</font color=blue>

 

[OCDLubeman]

Re: Why

My question: Is there a conventional 10w30 oil "on the shelf" at one of my local stores that is C rated?


It's pretty clear that most of the fleet oils that are C rated are also S rated - these tend to be 15w40 - I am not aware of any car manufacturers recommending 15w40. Correct me if I am wrong.

Also, I know that many of the synthetics/synthetic blend 10w30's are dual rated. But, their C rating usually is one of the older classifications - i.e., not CH4/CI4. But, the Kubotas only need a CD oil anyway. Maybe the mail order 10w30 oils are C rated (Amsoil, Shaeffers)? So, synthetic 10w30 would fit the bill for a Kubota.

But, I am confused - are you guys saying that you know of conventional automotive SJ/SL oils (usually 5w30 or 10w30) that also have a C rating? PLEASE TELL ME WHAT BRAND? My supplier says he can only get 10w30 C rated oil in 55 gallon drums. I'm looking for a few quarts.

Thanks,

Randy

 

[fractal]

Re: Why

Richard

The only dumb questions are the ones you don't ask. Especially since I was asking myself the same question. It all started when the wife picked up a "waste oil recycling container" at the "earth fair" the other day saying "you know, isn't it time you changed the oil in the tractor?". Well, I have put 50 hrs on it since the oil was last changed (the guy wrote the hours on the oil filter with a silver pen when he serviced the engine). I bought it last June and the guy I bought it from put 15 hrs on it between when he changed the oil and when he sold it, so it has been close to a yr on that oil, so I guess she is right.

I just checked the garage and sure enough that case of Castroil GTX is rated "SJ" but that case of Mobil 1 I bought for all those hard working 5 hp b&s motors is rated SJ,SH/CF. Funny how you can buy a case of mobil 1 at costo for the price of 2 quarts at the auto parts store.. My kubota D950-LA 4-cycle diesel is spec'ed for class "CC" or better. So, if I read the API spec pdf correctly, for a "CC" or better, I can run CC, CE, CF-4, CG-4 or CH-4 but NOT CF. Odd that.

Anyway, if I read the API doc correctly, up until about 1996 he probably COULD buy regular oil that was certified as both diesel and gasoline certified, so your uncle wasn't wrong. They just changed the oils 6 yrs ago so you can't do it any more.

The bummer is now I have to go out and buy 3.3 liters of yet another motor oil

 

[TresCrows]

Re: Why

Odd, my manual--2410 --says CC or CD. Mobil 1 is a CF oil. Very strange. J

 

[TresCrows]

Re: Why

That is also odd, it dropped my pic. J

 

[fractal]

Re: Why

You have a newer tractor than I do. I was looking in the Kubota Workshop Manual Tractor B5200-B7200HST. It called for service class CC. On the other hand, http://www.kubota.com/maintenance3.cfm specifies CC,CD and state that CF, CG-4 are accepted for use in Kubota products. So, guess that means mobil 1 is ok for use in a kubota.