Delvac, Delo, Rotella, or Kirkland 15w-40

JHZR2

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For a fleet of old Mercedes diesels and Cummins 5.9L engines. Any would be 15w-40. Which and why??

Go.
 
JHZR2 how long have you been on this site? You should know that any oil with the proper ratings from a major bottler will be more that sufficient.
 
JHZR2 how long have you been on this site? You should know that any oil with the proper ratings from a major bottler will be more that sufficient.
There is another thread on here about hpl engine cleaner. People use "spec oil" from a lube shop and end up with a coked engine. Oil is being reformulated nearly annually. What's wrong with looking for reviews on recent oils?
 
Delvac 1300, because it does the job and with the rebates has the best price. I was getting it as cheaply as $2.78 a gallon after rebate a couple years ago.
 
JHZR2 how long have you been on this site? You should know that any oil with the proper ratings from a major bottler will be more that sufficient.
Well… it’s because they’re all good. Like stated here:

I don't think you can buy a bad 15w-40. Use what's easiest to get or cheapest

Isn’t a bad philosophy. They’re all good, even the $22/3 gal (on sale) Kirkland HDEO.

Question is which and why? Cheapest is one option. Kirkland fits that bill. But it requires a Costco, and to buy three gallons (not necessarily an issue but just saying. So cheapest and hardest to get perhaps.

Rotella has been what I’ve generally gone with historically. I tended to find in the last that Delo seemed to return slightly lower fuel economy, but that was closing in on 20 years ago….
 
Delvac Extreme 15W40, it's full syn, around $20/gallon but they do the Delvac rebate twice a year and you can get back $9/jug on upto 4 jugs each time.
So that kind of fits in the thought process in my thread on 15w-40 vs 5w-40 in my low use car.

15w-40 syn is an option too… though I think if I’m paying for syn I should be paying for the better startup flow of a 5w-40, because even in my trucks, I haul heavy sometimes, but not terribly far or on challenging terrain, so the benefit of a syn 15w-40 in terms of robustness isn’t a major factor.
 
So that kind of fits in the thought process in my thread on 15w-40 vs 5w-40 in my low use car.

15w-40 syn is an option too… though I think if I’m paying for syn I should be paying for the better startup flow of a 5w-40, because even in my trucks, I haul heavy sometimes, but not terribly far or on challenging terrain, so the benefit of a syn 15w-40 in terms of robustness isn’t a major factor.
The 15w-40 Delvac Super 1300 is a semi synthetic. It's cold pour point is-33c. I looked up the Mobil 15w-40 Delvac Extreme that is a full synthetic and it's pour point is the same at -33c!! It does have a higher TBN 10.6 to the semi syn's 9.6. Do you think it's worth an extra 6 or 7 dollars a gallon? Also, the I saw a VOA on the Kirkland's diesel sold at Costco and it had a TBN of 10. I don't remember what the cold pour point is but I'll bet it is close to the Delvac Super 1300 15w-40 semi syn. Unless the weather where you live gets below -30c you should not have a big concern about the normal cold temps you get in New Jersey. -30c is -22F in case you are interested. 15w-40 HDEO for the win!!
 
supertech diesel. cheapest one and its both ford wss and volvo vds certified. Delo and delvac are just vds certified and fords wss is supposedly pretty strict in wear protection.
I thought that Ford standard was mostly Ford's disagreement with the API about minimum ZDDP levels and it's mostly just CK-4 with 1000ppm minimum phos requirement, I think it says more about the Ford PSD design than it does modern oils having lower phos levels, is there any proof that the Benz engine or a Cummins needs higher zinc.
 
The 15w-40 Delvac Super 1300 is a semi synthetic. It's cold pour point is-33c. I looked up the Mobil 15w-40 Delvac Extreme that is a full synthetic and it's pour point is the same at -33c!! It does have a higher TBN 10.6 to the semi syn's 9.6. Do you think it's worth an extra 6 or 7 dollars a gallon? Also, the I saw a VOA on the Kirkland's diesel sold at Costco and it had a TBN of 10. I don't remember what the cold pour point is but I'll bet it is close to the Delvac Super 1300 15w-40 semi syn. Unless the weather where you live gets below -30c you should not have a big concern about the normal cold temps you get in New Jersey. -30c is -22F in case you are interested. 15w-40 HDEO for the win!!
Yeah … FF in DMax and CAT in another drum…
 
The 15w-40 Delvac Super 1300 is a semi synthetic. It's cold pour point is-33c. I looked up the Mobil 15w-40 Delvac Extreme that is a full synthetic and it's pour point is the same at -33c!! It does have a higher TBN 10.6 to the semi syn's 9.6. Do you think it's worth an extra 6 or 7 dollars a gallon? Also, the I saw a VOA on the Kirkland's diesel sold at Costco and it had a TBN of 10. I don't remember what the cold pour point is but I'll bet it is close to the Delvac Super 1300 15w-40 semi syn. Unless the weather where you live gets below -30c you should not have a big concern about the normal cold temps you get in New Jersey. -30c is -22F in case you are interested. 15w-40 HDEO for the win!!
By the pour point logic, Kirkland pours to -36C, even colder.

Daimler on the other hand doesn’t permit 15w oils anywhere near as low.


The rotella semi syn looks interesting because it has high zddp, some moly and other good adds from the PQIA VOA.
 
By the pour point logic, Kirkland pours to -36C, even colder.

Daimler on the other hand doesn’t permit 15w oils anywhere near as low.


The rotella semi syn looks interesting because it has high zddp, some moly and other good adds from the PQIA VOA.
Pretty much all the Rotella HDEO except the multivehicle uses a similar add package and should have around 1100ppm of phos, Delvac Extreme should be near 1200ppm.
 
I thought that Ford standard was mostly Ford's disagreement with the API about minimum ZDDP levels and it's mostly just CK-4 with 1000ppm minimum phos requirement, I think it says more about the Ford PSD design than it does modern oils having lower phos levels, is there any proof that the Benz engine or a Cummins needs higher zinc.
Even if it were true that ford doesn't do diesel oil testing and that it must have 1000ppm zddp it couldn't possibly hurt to have 1000ppm instead of 800 in the same diesel oil anyway. But ford does have actual test. And the article says 1000 hour and talks about phosphorous and not zddp anywhere which is weird. It's astm WK72778.

And this is an old article about it~ https://www.fuelsandlubes.com/ford-6-7l-valve-train-wear-test-to-be-completed-by-the-first-quarter/
 
Would a 10w40 E6 or CK-4 be on your radar? Only in Canada eh?
I bought 2 20L pails of Duron 10w40 CK-4 last year, still un-opened for a 2018 L5P Duramax.
 
Even if it were true that ford doesn't do diesel oil testing and that it must have 1000ppm zddp it couldn't possibly hurt to have 1000ppm instead of 800 in the same diesel oil anyway. But ford does have actual test. And the article says 1000 hour and talks about phosphorous and not zddp anywhere which is weird. It's astm WK72778.

And this is an old article about it~ https://www.fuelsandlubes.com/ford-6-7l-valve-train-wear-test-to-be-completed-by-the-first-quarter/
and ZDDP is the primary phosphorous containing compound in motor oil, in the case of talking about phos limits, largerly ZDDP levels and phos levels are synonymous.
Also I've never heard anyone refer to the C category as meaning Commercial and the S rating as "Service", I was always under the impression the C rating was C for compression ignition engines and S was S for Spark Ignition engines.
 
Since you are not running a Ford Diesel engine, you can use any API approved CK4 or CK4/SN 15W40 diesel oil. It really doesn't matter as long as the oil has all the appropriate approvals for your engine(s). I would use whatever major or house brand conventional diesel oil that is the most cost effective. Given the rebates, Mobil Delvac 1300 Super is among the low cost diesel oil leaders. As stated earlier, Delvac 1300 Super is a dual CK4/SN approved diesel oil with a lower phosphorus level of 800PPM to meet the gasoline engine SN rating. In addition to Mobil, both Chevron and Valvoline offer dual rated CK4/SN diesel oils. It's my understanding that these oils make use on other nonmetallic additives to supplement the lower phosphorus levels to provide good wear protection.

Ford is the only manufacturer that I am aware of that has not approved the dual rated CK4/SN lower phosphorus diesel oils which raises the question: is it the oil or an issue with 6.7L Powerstroke engine design/metallurgy. To date, Ford has not provided sufficient data to make a clear determination.
 
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