TOP DOG® CK-4 SAE 15W-40 is a premium, high performance, mineral oil based heavy duty diesel engine oils meeting the latest API CK-4 Heavy Duty Diesel performance specification making it suitable for use in the latest engines produced by major OEMs including Cummins, Caterpillar, Detroit Diesel and Volvo/Mack. TOP DOG CK-4 SAE 15W-40 is also backwards compatible with other API Heavy Duty Diesel performance categories such as CJ-4, CI-4 Plus, CI-4 and CH-4.  Being a low SAPs oil, TOP DOG CK-4 SAE 15W-40 provides protection for exhaust after-treatment systems including Diesel Particulate Filters (DPF) as well engines using AdBlue (SCR) technologies.