3-cyl diesel : tractor : 10W-30 vs 15W-40

[JGY]

I have a John Deere with a 3-cylinder Yanmar diesel engine. The OM calls for "preferred" John Deere Plus-50 10W-30 DEO. (The 5W-30 is called for below some unimaginable low temperature.)

I live in and operate the tractor in SC -- hot humid SC. Temperatures can easily reach 100+ degrees in the summer (not to mention lower 90's in late spring and fall.)

My question is "Should I continue to use the 10W-30 oil or switch to 15W-40 oil because of temperature?"

Any thoughts, feelings, rants, raves, criticisms, praises, etc., on the issue are welcome ....

Joe

 

[Johnny]

I'll just give you my thoughts, I will leave the rest of the emotions for others.

For that hard working little 3-cyl diesel, in your summer conditions, I would use a 15W-40 or one of the good 5W-40 diesel oils.

 

[Eddie]

I probably would use what the manufacture recomends.

 

[JGY]

... and that's the rub.

The OM states the preferred oil as a 10W-30. The OM states that one should choose the viscosity based on the temperatures expected until the next OC.

10W-30 oil, according to the temperature chart provided by the manufacturer of the tractor, is good up to a temperature of 104 degrees Fahrenheit. 15W-40 oil is good up to a temperature of approximately 122 degrees Fahrenheit.

Conflicting information?! ....

Am I to interpret the OM this way: "preferred" John Deere Plus 50 15W-40 Supreme Motor Oil? It is a "preferred" oil, it meets the viscosity requirement for "highest" temperature.

Thanks for the response,

Joe

 

[soldierman]

I've got a yanmar powered JD mower and I run 15w40 in mine.

 

[TiredTrucker]

Being you're in S.C., you could easily get by with a straight 30 diesel oil. Barring that idea, you can find darn good prices on a Xw40 diesel oil in the brand of your choice that will work just fine. 5w40 will work just as well as 15w40. Contrary to popular opinion, they only differ in winter flow rating. They are both 40 weights. Don't get too bound up in technicalities. Stay with the grade and brand you like and you will be fine.

I have used a 15w40 in my New Holland tractor with a 3 cylinder diesel for a number of years... year round in Iowa. I do plug in the block heater in the winter, but I have never had a flow problem. Unless you are going to experience temps of below 0F for extended periods of time, you would have no problem with a 15w40. I have my tractor plugged in and it will start fine and oil pressure comes right up even at -20F using 15w40.

 

[Jim Allen]

I have a 3-cyl diesel tractor, a Ford Dagenham-built 2810. I was running 15W40 R-T with no trouble for the most part. I switched to 10W30 a coupla years ago. Why the "downgrade?" It's used as my utility tractor all year round. It does a lot of starts and stops, sometimes never getting fully warmed up. It does NOT have an oil cooler (which will double as an oil WARMER in cold weather). I had a cold start issue one winter (due to spinning over too slowly and I can't always plug it in) so I switched to the lighter oil. I also figured that with it's relatively light loads and "short hop" use, the lighter oil was appropriate, flowing better at those low oil temps (at 150 degrees, a grade 30 is nearly a grade 50). I measured the hot oil pressure with 40 and with 30 and it dropped only fractionally. The lighter oil might give me fractionally better fuel economy too.

My opinion is that if your tractor is used the way mine is, a 10W30 is appropriate and more than adequate protection. If your Yanmar has an oil-to-liquid oil cooler, the 15w40 would warm up faster and be less a "drag." If you use your tractor hard and for hours on end (as I do my big International), 15W40 is the better choice. In your climate, I'm not sure it will make a whole lot of difference either way. The 10W30 won't help you all that much but 15W40 isn't of any huge benefit either. After my long parsing of the topic from my POV, I guess I'm saying get whatever you can find easily.

 

[Steve S]

I have a John Deere as well with a 3 cyl Yanmar engine and the manual has a SAE type oil chart and 10w30 is good up to around 80 or 90F. Straight 30 goes a bit higher. I can get 15w-40 cheaper at Walmart or Costco than going to the Chevron jobber here to get Delo 400 10w-30. Since I sold my acreage the tractor doesn't really get workrd hard.

 

[JGY]

Thanks for all the good information ....

BTW I use the tractor at s-l-o-w speeds 95% of the time cutting grass, two to three times a week, usually for several hours at a time. That is probably considered s-e-v-e-r-e use, requiring servicing much more often. The tractor has no oil cooler -- either for the engine or hst/hydraulic pump.

As of today, I average about 36 minutes of use a day. The tractor is not a year old yet (182hrs/304days).

Joe

 

[opposite_locker]

We run Delo 15w40 in all our farm equipment: tractors, backhoes, shakers, sweepers, harvesters, etc...

I believe it costs just under $10/gallon if purchased in 55 gallon drums.

The 15w40 will be a better oil in any conditions you will face. Only reasons manufacturers always recommend the lowest viscosity oil is the potential for lawsuits or warranty repairs if operated with a 15w40 in sub-zero temps.

 

[Rob_Roy]

We always ran 15w40 in our JD332 mower which had the 3-cyl Yanmar diesel.

 

[RWEST]

Quote:
(The 5W-30 is called for below some unimaginable low temperature.)

Heheheh. In SC, what's that, about 35 degrees?

I remember spending lots of time on Hilton Head Island, and any temp below about 50 had the locals dressed like they were in Alaska..

In any event, J-D markets some really good lubes, so, if they offer a 10-30 - I'd have no problem using it. For my own use, their 0w-40 synthetic makes for much easier startups when the mercury's fallen out of the bottom of the thermometer.

Like the guys have posted, it's hard to find a 'bad' DEO.

 

[dnewton3]

I'd tend towards the 15w-40 in your location; just doesn't cold enough to warrant the 10w-30 grade.

I'm on the opposite end of the spectrum with my Kubota L3430GST; I run Rotella 10w-30 year round because it get's below zero, and I have to plow the 1/2 mile driveway. But it rarely get's over 100 degF in summer.

Besides, if you knew of the abuse and poor quality lubes that Yanmars experience in third-world countries, you'd not worry so much. Some of the junk and extreme OCIs make me shudder. And yet they keep on running. You'll baby your little Deere, and it likely won't make any difference at all in the lifespan between 15w-40 and 10w-30.

As always, if you want "proof", then do some UOAs and experiement.

 

[OVERKILL]

I've had great luck with AMSOIL 15w40 in this engine.