10w40 in a Cummins 5.9L Six

[Dad2leia]

Among my many questions, here comes one for the diesel engine in my family. Living here in PA, winters can get rather cold. On this note I ask if anyone has any comments about using a high quality 10w40 motor oil, sprucing it up with Specialty Formulations SX-UP additive, and getting the little extra cSt range on the cold end, and NOT doing any harm to the engine.

Being a Cummins, they ONLY will spec 15w40 HDEO year 'round, no matter what the temperature is outside. The engine does have a block heater, which I faithfully plug in when the temps are 38F or colder, and will leave it plugged in, even if I don't plan to start it that day.

I also already have an oil in mind brand wise, so fire away with this logic.

 

[Ken2]

NO! Use a CI-4 or CI-4 Plus synthetic 5W-40 for winter. A gasoline engine oil is not robust enough for your diesel engine.


Ken

 

[Bio-T]

If you feel the need for a winter oil, I recommend a 5W40. Shell Rotella, Schaeffers, Chevron, DelvacI, Mobil 1 Truck/SUV and other CI, CI+ rated diesel oils.

Now, all these oils can be used year around with excellent results.

Why the 10W40? I will never again consider anything other than a 15W40 or 5W40 in a diesel, unless I lived in arctic areas.

JMO

 

[Ken2]

Vette,
Soon the standard oil in diesels will be diesel-spec 10w30. It is part of the global effort to conserve fuel. In any case, it will be diesel spec, not gasoline engine 10w30. We'll really need a new viscosity rating system to minimize confusion.


Ken

 

[Dad2leia]

I considered the 10w40 because this truck just turned 100K on the odometer, and I didn't think that 5w40 would be the way to go since it's only seen 15w40 for its life so far.

The 10w40 I was considering was Maxima Extra 4 synthetic. I've checked out the specs, and have talked about the additives, plus I thought with using the SX-UP, would make this a fine, robust oil that would be suitable? Yes, no...?

 

[Bio-T]

Ken,

I was not real clear on my post, my fault. I won't use 5W30 or 10W30 diesel oils in my present diesels.

 

[brian fix]

Mystik makes a 10w30 diesel mineral oil,thats a good lube,,,Schaeffers 5w-40 9000, (check with site sponsor) thats REALLY good oil,the 15-40 Schaeffers pour point is -41,,pump is around -25,though there many choices,,Amsoil is also a consideration......BL

 

[bulwnkl]

I haven't talked to Maxima like you have, but just looking at their website and knowing their products somewhat from my dirt-biking days, I'd say they're making a pretty good product that I would NOT put in a Cummins diesel engine that specified a compression-ignition engine oil (i.e. CF, CH, CH-4,...CI-4+). Molakule could tell you whether his SX-UP would give it what it needed in terms of D-D and other adds to work, so just ask him directly at his office.

If you're concerned about winter temps there are several good alternatives that come to mind:

1) Add a magnetic (or other) oil pan heater. Then you can use the 15W40 without worry.
2) Use a 5W40 diesel-spec oil. Several were mentioned above.
3) Use a 10W30 diesel-spec oil (Rotella T, Delo 400, & Delvac 1300 Super dinos all come in 10W30. There are synthetic choices available as well.). Find a big truck stop or call an oil distributor. Shoot, even one of the mini-mart gas stations up north of here stocks Delo 10W30 in gallons.

These are just a few choices that come to mind to address the issue you presented without the potential for destroying or prematurely killing that Cummins engine.

 

[TomJones76]

Hey, if Schaeffers 15W40 has a pumping temp of -25, wouldn't that make it either a 5W40 or a 10W40?
I thought that SAE rules demanded you not label something pessimistically or optimistically for either winter or standard viscosity.

 

[Dad2leia]

bulwnkl, I do have a block heater that came from the factory, so that isn't a concern. I didn't want to go ith a 5w40 due to the mileage and the fact that it has only seen 15w40 from day one. I figured that 10w40 was a happy medium in that I still will have the viscosity desired by the manufacturer in the 40 weight, but have some extra pumpability and temperature range in the 10w weight spec. I realize that on the site they specify SG/CC for that oil, which is why I thought that the additive pack would be boosted enough with MolaKule's product.

I guess i'm trying to make a mole hill out of a mountain with this contemplation, eh?

 

[TomJones76]

As a point of useless trivia, there *IS* at least one good diesel oil in 10W40.
Go to:
http://www.rotella.com/products/index.php
Look at the fourth product down.
Shell ROTELLA® T Synthetic-Blend is available in 10W40, 10W30 and 0W30.
The 10W40 only has a TBN of 9.7 though, which strikes me as odd versus the 11.5 in both 15W40 conventional and 5W40 synthetic.
I've never seen Rotella T Synthetic Blend.
Has anyone ever seen it?

 

[bulwnkl]

quote:

---

Originally posted by Dad2leia:
bulwnkl, I do have a block heater that came from the factory, so that isn't a concern. I didn't want to go ith a 5w40 due to the mileage and the fact that it has only seen 15w40 from day one.

---

Yes, I can understand that. And I know that neither 5W40 nor xW30 are recommended. I wouldn't anticipate problems with the 5W40 at all, and I wouldn't anticipate problems with the 10W30 in COLD weather if it's used as a passenger car like most pickups.

The reason I suggested a magnetic oil pan heater is that I am not aware of how warm the block heater in that engine keeps things, so I don't know whether it will keep the oil above ambient or not. I am familiar with Cummins and CDC engines in tractors and heavy trucks, and they may not be the same. Anyway, assuming COLD weather, I'd want an oil heater. The block heater may provide some benefit, but it is mostly there (in some other applications) to keep the block and cylinder head temps high enough to ensure quick cranking and good light-off. As you probably know, below a certain ambient temperature (which varies with the engine design) a diesel engine will not generate enough heat to light the fuel. Keeping the block and head warm ensures that there is plenty of heat in the CC to light the fuel, but the oil may still be a bit thick.

$0.02

 

[Dad2leia]

Yep, I'm aware of that. I'm not sure how warm it makes the oil, but it works rather well with the cylinder bore and heads, because she fires right up even on the really cold days.

That is the biggest reason I was looking at the 10w40, pumpability AND viscosity protection for HT/HS and film strength.

 

[RichR]

quote:

---

Originally posted by TomJones76:

I've never seen Rotella T Synthetic Blend.
Has anyone ever seen it?

---

When I had a cummins Dodge I used Rottela SB in the winter.I used 10w30 and it did make for easier starts in cold over the 15w40.I could not plug it in at work over night.
I bought it at a Shell distributor and at a Farm and Fleet store.
This was four years ago pre Bitog for me so I can't help with any hard data.
Rich

 

[Dad2leia]

Well, after conversing with MolaKule, it seems that with using his SX-UP product and the Maxima oil, I have a "winner", so I think that I'll good to go with this combination.

I can safely say that MolaKule has probably forgotten more about lubrication then I'll EVER learn!!!

 

[rpn453]

quote:

---

Originally posted by bulwnkl:
And I know that neither 5W40 nor xW30 are recommended.

---

For 2003 and newer (and maybe even a few years prior, I've only seen the manuals for '03 and '04) Dodge specifies that a 5W-40 CI-4 oil may be used provided it's full synthetic.
My buddies with Cummins' take it one step further and use Esso XD-3 0W-40 in the winter. Here's a UOA for one:

http://theoildrop.server101.com/ubb/ultimatebb.php?ubb=get_topic;f=26;t=000179#000000

 

[Rebel Rouser]

Kudos to Cummins with the intake grid heater system on these engines.

I have a 5.9L ISB in a Dodge, and I routinely do not use the block heater, and this thing has started reliably, on the first cycle of the grid heaters, even when temps are well below 0F. The truck is not garaged either.

I've run full synthetic 15w40's and
Delvac 1 in the past, and based on UOA, my engine is none the worse for wear doing this. I currently have Schaeffer's Supreme 9000 5W-40 in the crankcase for the upcoming winter. An excellant oil, that's not priced out of this world.

 

[Dad2leia]

I have no qualms about the Schaeffer's Line, as a matter of fact, I've used their Supreme 7000 5w30 before in my other vehicle. I just love to try different things from time to time.

I guess you could call me a mixologist, but mixing brands for oil changes

(Yes I have mixed different viscosities from time to time as well, trying to find that "magical brew")

 

[oil pan 4]

Every diesel engine we have from the little heaters powered by a 1 cyl. diesel also lots of 2 and 3 cyl ones (powering air compressors and generators) all the way to V-6 detroit diesels and cummins 5.9L's.
They all get the same straight 30 weight oil.
It never gets below 20'F here, I think the tech data says to use that kind of oil unless it get's to 0'F. That goes for all enigines gas or diesel.
Our 5.9L cummins trucks were made in 1990 and 1991 and they still run great.
A lot of the other smaller diesel have been around about 10years or less.

 

[KJA426]

I'm no expert but I'd stay with a 15w40. My neighbor had it in his 2.5 Jeep last winter and we had some bitter cold mornings. Granted, it was only in there because he didn't bother to have me change it in the fall. He's the type that just runs a car with no preventive care unless I harp on him to let me change the oil, plugs, etc.