Synthetic Mobil 1 15W-40 vs 5W-40 Truck Diesel oil?

[mswlogo]

I can't decide between these two oils. I suspect either would be fine but I'd like some opinions.

I don't put many hours on the tractor, 10 hours per season. I mostly just maintain a dirt road with it during the warm season.

I may run it as long as the ground is not frozen (Central NH).

So I don't really need the 5W for super cold starts.

And when I do run it, it could be very hot for 5 hr's of a box blading.

So I thought 15W-40 would be a better range.

However the 5W-40 is design specifically for Diesel and the 15W-40 is not.

The 15W-40 is CF rated though which is Kubota's only requirement.

I plan to change oil every other season (about 20-25 hrs). It's crazy to change it after 10 hours use.

I want to run Full Synthetic.

 

[KennyV]

Some things to consider when choosing oil...
Your First choice should be an oil made FOR Diesel engines.
Second it should be a synthetic.
Third should be a low first number compared to a higher second number.

And no matter who's oil you use, change it at least once a year. (it will not shear down, with low hours, But the PH will likely not be stable over Two years....

Look into oils & how they work inside an engine, you will see why...
Some may feel that almost any oil will do the job your asking of your equipment... 10 hours a year, you Could change the oil every 15 to 20 years and be okay...
That may work... and then it may not...
I would go with the best synthetic & change it once a year...
but from your 2 choices... I'd pick the 5w-40, it includes the first consideration & the third... KennyV

 

[PHILIP8N]

I will keep this simple since it appears to me you have decided on Mobil oils.

Mobil 1 TDT 5w-40 is rated for temps from -22F to 122F, is acceptable for use in your diesel engine, and available at many stores.

Mobil Delvac 1300 Super 15w40 is rated for temps from 15F to 122F, is acceptable for use in your diesel engine, and is available at many stores.

Pick your ambient conditions and go.

For me personally, I use the M1 TDT 5w-40 because I use my tractor year round in temps from 0F to 95F. I do about 50 hours a year, and change my oil every other year.

Philip

 

[BeezFun]

I don't think Mobil1 15-40 is properly rated for your engine. You probably need CI or higher, which would limit you to the turbo diesel version. As I recall Mobil 1 has some low C rating like CD or CF which would be OK in a car diesel but probably not good enough for a tractor.

 

[PHILIP8N]

I don't think Mobil1 15-40 is properly rated for your engine. You probably need CI or higher, which would limit you to the turbo diesel version. As I recall Mobil 1 has some low C rating like CD or CF which would be OK in a car diesel but probably not good enough for a tractor.

There is not an oil called 'Mobil1 15-40'.

Mobil Delvac 1300 Super 15w-40 is a HDEO and is fine for 30 hp Kubota and 800 hp Caterpillar engines. It carries an API rating meeting or exceeding CJ-4, CI-4 plus, CI-4, CH-4, SM, and SL.

Mobil 1 TDT 5w-40 is a HDEO and is also fine for 30 hp Kubota and 800 hp Caterpillar engines. It carries an API rating meeting or exceeding CJ-4, CI-4 plus, CI-4, CH-4, CG-4, SM, SL, and SJ.

Nice input.

Philip.

 

[greasemonkeyok]

It is not crazy to change your oil after 10 hours of use if the oil has been in the engine for one year. Time alone has an adverse effect on the oil, which is why they have a calendar time ceiling on its use in addition to the clock time ceiling. The degradation is primarily due to base oil oxidation.

You might want to take a gander at:

Basic Lubrication Design - Bob is the Oil Guy

 

[mswlogo]

I will keep this simple since it appears to me you have decided on Mobil oils.

Mobil 1 TDT 5w-40 is rated for temps from -22F to 122F, is acceptable for use in your diesel engine, and available at many stores.

Mobil Delvac 1300 Super 15w40 is rated for temps from 15F to 122F, is acceptable for use in your diesel engine, and is available at many stores.

Pick your ambient conditions and go.

For me personally, I use the M1 TDT 5w-40 because I use my tractor year round in temps from 0F to 95F. I do about 50 hours a year, and change my oil every other year.

Philip

I didn't say Delvac (I believe that is dino oil). But looking on Mobil's web site I can't find 15W-40 Mobil 1. But Walmart sells it.

I choose Mobil 1 because it's fairly easy to get and not crazy expensive.

Mobil also has a pretty wide range of applications.

I actually put Castrol LL03 long life oil in my VW and can only be purchased at a VW dealer and is $8 a quart. But I go 10K per oil change. I have been running Mobil 1 for all my cars for a long time. But my Jeep developed a normal lifter tapping problem (it has 200K) and I tried Castrol Synthetic Titanium and it eliminated the tapping (same weight !!).

But I don't see a 15W-40 or a Catrol Synthetic specific for Diesel engines. Some castrol's are not easy to find either.

Amsoil makes a 15W-40 Synthetic designed for deisel. But nobody locally sells it and you pay double plus shipping buying it online.

I wish I could find specs on the Mobile 1 15W-40.

I used to run 5W30 in cars. Never a problem. But wow, when hot that stuff is like water.

If the engine is not designed for that low a viscosity it makes me nervious. They cars were spec'd for 5W30. The Kubota is not spec'd for 5W40. Even though it meets the ratings.

I also don't know if diesel oils have different additives for diesel engines. I don't think it's just marketing. The diesel oil does meet a ton more specs then the 15W40 Mobile 1. So I really want to understand the difference.

The key part of oils today are the correct additives for the application. Not just visocity.

About the only two places that carry good selection is AutoZone and Walmart and usually Walmart has much better selection and better price.

I'm not dumping good oil after 10 hr's. Been going 2-3 season on chippers and rototillers etc. For 30 years and never a problem. I was doing it yearly but I was pooring oil out that was as clean as what was going in. That's just dumb and wasteful. Even my boat I do it. Supposed to change oil and transmission every 50 hr's, lucky if I get 10 hr's on it a season.

 

[Gale Hawkins]

Flip a coin. If you happen to change you own oil in your other machinery, it would be easier to stock just one oil for everything as I do. NH = 5W-40 :thumbsup:

BINGO

This is the reason we went with Rotella Synthetic 5W-40 so it is good for the push mower through diesel BH and tractor. The 429 and 454 need the higher zinc levels.

 

[PHILIP8N]

I didn't say Delvac (I believe that is dino oil)

Delvac is a heavy duty brand under the Mobil name. Delvac is available in mineral, semi-synthetic, and synthetic. Here are the oils under the Delvac brand.

Mobil USA | Heavy-Duty Engine Oils | Mobil Delvac Engine Oils

But Walmart sells it.

I have only seen the Mobil Delvac 1300 Super 15w-40 at Walmart. Walmart also sells Mobil 1 TDT 5w-40.

I wish I could find specs on the Mobile 1 15W-40.

There is no such thing as Mobil 1 15w-40. BeezFun was incorrect in his post.

If the engine is not designed for that low a viscosity it makes me nervious. The Kubota is not spec'd for 5W40. Even though it meets the ratings.

Who said the engine is not designed for low viscosity? The Kubota specs are poorly written and need updated. I have attached the viscosity requirements for a Caterpillar engine. They are very clear, and if studied, make very good sence. Just think, a 5w-40 and a 15w-40 oil have the same viscosity at 122F ambient, so they both provide the same high temp protection.

I also don't know if diesel oils have different additives for diesel engines. I don't think it's just marketing. The diesel oil does meet a ton more specs then the 15W40 Mobile 1. So I really want to understand the difference.

Yes they do, hence the API Cx rating system. Again, no such thing as Mobil1 15w-40.

The ONLY oil on my shelf for ALL of my 4 stroke internal combustion engines is 5w-40. Not being mean, just honest, you are a little 'engine oil' challenged. Thats okay, just keep reading and learning. The website listed in another post, 'Bobistheoilguy', has a great deal of good information. In the mean time, go back to my original post, keep it simple, pick your minumum starting temperatue, and pick one of those two oils.

Good luck, Philip.

 

[BlacknTan]

I'm running Mobil Delvac 1 full synthetic, and I'm very happy with it. I've been using fully synthetic Mobil 1 for years now in gas engines, now Delvac 1 in deisel.