Results for a Fourth Group of 15W-40s are in

The results are in on four more heavy duty diesel engine oils, and the tests conducted on the samples meet the SAE J300 specifications for the SAE Viscosity Grade listed on the product label, and are consistent with the listed API Service Categories, or in the case of the Ford Motorcraft motor oil, the listed OEM specifications.

It’s important to note that Ford Motorcraft did not make the move to API CK-4 due to concerns about wear issues related to the lower phosphorus levels specified in CK-4. In a position statement, Ford said, “Ford will not be recommending the use of CK-4 motor oils in any Ford diesel engines, new or old. Ford testing has shown some CK-4 type formulations have shown inadequate wear protection compared to CJ-4 formulations developed and licensed before 2016. Ford now recommends using oils that meet our OEM specification, Ford Material Engineering Specification WSS-M2C171-F1.”

It should also be noted that although John Deere PLUS-50 II™ API CK-4 is in the market, the product was not available at the John Deere dealers visited by PQIA in June 2018. Instead, PQIA only found CJ-4/SM available.


CAT15W40 Kubota15W40 JDPlus50II15W40 Motorcraft15W40
CAT DEO-ULS Kubota John Deere Plus-50 II Ford Motorcraft Super Duty Formula

Other API CK-4s recently examined and reported on by PQIA

The following are other HDEO API CK-4 brands on retail shelves recently examined by PQIA. The test results for each of these brands all meet the SAE J300 specifications for the SAE Viscosity Grade listed on the product labels, and are consistent with the listed API Service Categories.

The data and assessments for these brands can be seen by clicking on the images of the products below:
ChevronDelo400SDE15W40 MobilDelvac130015W40 PCDuron15W40 ShellRotellaT415W40
Chevron Delo 400 SDE Mobil Delvac 1300 Super Petro-Canada Duron HP Shell Rotella T4
ValvolineHDD15W40 KendallSuperDXA15W40Front Duragard15W40Thumb ValvolineBlue15W40CK4Front
Valvoline Kendall Super-D XA Duragard Diamond Plate Premium Valvoline Premium Blue
CarQuest15W40 Lubrigaurd15W40 STP15W40 OReilly15W40
CarQuest Warren Oil Company Lubriguard STP Pro Formula O’Reilly
Traveller15W40 RoyalPurpleDuralec15W40 Napa15W40
Traveller Royal Purple Duralec NAPA Premium Performance


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