10W40 in diesel engine.

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If a store had a blowout of a certain synthetic blend 10W40 gasoline oil at $4/gallon what would be the harm in running in a large 15L caterpillar or cummins engine? Sump is 10 gallons so oil would cost $40 vs $150 for conventional 15w40 this would be a one time thing due to the limited quantity of the blowout/clearance price. i do oil changes at 10000 which is usually every 3 months. engines are from the 1990s..so maybe the current 10w40 is better than the oil they seen in the 90s?
 
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The oil is way better, but it is still gasser oil. It doesn't have anywhere near the ability to handle the soot a diesel oil does. False economy. I have to tell this to myself often, but my stash is much more manageable now. "It's only a deal if you can actually use it." If you have to run the wrong spec, or blend it to make it work, pass.
 
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Originally Posted By: KCJeep
The oil is way better, but it is still gasser oil. It doesn't have anywhere near the ability to handle the soot a diesel oil does. False economy. I have to tell this to myself often, but my stash is much more manageable now. "It's only a deal if you can actually use it." If you have to run the wrong spec, or blend it to make it work, pass.
I agree with KC, I only buy blow outs and specials if they are in my grade.
 
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I tried 10W40 PCMO in my 2011 Duramax followed by a UOA. The only concern was the oil sheared down considerably after 6,400 miles. Expect better gas mileage. I found a 7% improvement over 15W40, but the cold start performance seemed to get worse as the oil aged. I would run it again but change it out at 50% of the OLMS.
 
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krismoriah72

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what is the 'difference in diesel vs gasoline oil'? from what i see to 'handle soot' its the additives? Since i cant find a virgin analysis of the 10w40 im looking at i will use the same brand in 10w30 that i saw from another analysis. these arent virgin but used.. additives in the 10w30 - calcium 2149 phosphorus 653 zinc 758 additives in supertech 15w40 calcium 1103 phosphorus 1026 zinc 1203 what are the additives that turn oil into 'diesel oil'?
 
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Keep in mind that any motor oil is a mixture of a pure base oil plus a package of many additives. Set aside the names of the additives and look at the requirements they need to meet. This link shows the testing for gasoline engine oils and the different tests required for diesel engine oils. http://www.infineum.com/media/80723/api-oil-engine-classifications-2013.pdf Infineum is one of the chemical companies that make the additive packages for motor oils. Infineum is owned by by Royal Dutch Shell & ExxonMobil. ChevronOronite is another. Lubrizol. Afton Chemical. And a few others. https://www.oronite.com/products/gf5.asp https://www.oronite.com/products/OLOA61005.asp
 
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I would not do it! not in that big of an engine stick with a HDEO it has dispersants for soot handling and better detergents and add pack, etc.etc... no way not me.
 
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Originally Posted By: beanoil
Better off with a sale from AA when they run Peak on sale for 9.98 a gallon. You need a diesel oil to handle the soot.
And it depends on which Peak coolant it is also that one puts in that diesel. A lot of the regular Peak coolants designed for autos do not provide the cavitation protection for wet sleeve liners and proper lubrication for heavy diesel water pumps. The only Peak branded coolant that is going in my heavy diesels is the Final Charge Extended Life Coolant, no nitrite formula. It is not wise to play "what if" games with heavy duty engines. And anyone who is that spend thrifty that, just to save a few bucks, is going to drop in an oil not made for their class of engine, then they have some serious money issues and they had better sell the truck. If financials are in that bad of shape, then best to sell the truck and shut down the operation.
 
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A bit OT, but ironically our diesel mule calls for a 10w40 meeting the CJ4 spec IIRC. Didn't know they made such a thing.. Lol. It has gotten 15w40 dino and 5w40 M1 TDT its whole life.
 
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Mystik is a darn good performer. I have used it in the past in commercial engines with great results. If I wasn't getting a very high quality oil in bulk at a lower price, I would have no problem filling with Mystik products. Lots of farmers and rural property owners use Mystik products. That is why you can readily find them at Farm and Home stores. If they didn't do the job great, they would be yanked from those shelves in short order. "name" brand? Mystik is made by Citco. They are not a name brand?
 
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Originally Posted By: Ken2
Mystik is good, limited distribution, many parts of the U.S. have never seen it.
That is the rub. It is not usually in the average auto parts store and I don't think any Big Box store like Wally World has it available. It has a niche market with Farmers and rural folks and commercial applications. And all of those folks can put an oil to the test in their applications. Mystik does quite well.
 
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Originally Posted By: dlundblad
Ehhh. Ill stick to a "name" brand. smile
Tractor Supply has Shell Rotella T5 10w40. Shell is a huge name brand.
 
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Originally Posted By: used_0il
I tried 10W40 PCMO in my 2011 Duramax followed by a UOA. The only concern was the oil sheared down considerably after 6,400 miles. Expect better gas mileage. I found a 7% improvement over 15W40, but the cold start performance seemed to get worse as the oil aged. I would run it again but change it out at 50% of the OLMS.
Wow, you are braver than me and must not care about longevity. This is the one reason I hate buying used because one never knows what mistakes the previous owner has made.
 
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