RIDGELINE™ SAE 15W-40 CK-4 is a high performance,
full synthetic heavy duty engine oil formulated for
modern diesel powered engines operating across
a range of severe applications. This oil offers
excellent shear stability and is reliable for
extreme cold engine start-up. Advanced API CK-4
additive technology is fully backwards compatible
with, and replaces, service categories CJ-4, CI-4 Plus,
and previous.