Schaeffer's API Service Category CJ-4 is for use in high-speed four-stroke cycle diesel engines.
It is designed to meet 2007 model year on-highway exhaust emission standards as well as for previous model years. Schaeffer's oils are designed to exceed the CJ-4 category requirements.
Please note: This category is mostly being replaced by the newer CK-4 Schaeffer’s SynShield® engine oils. Schaeffer’s Supreme 9000 5W-40 is moving into the CK-4 category and has a new name. Schaeffer’s SynShield® OTR Plus Full Synthetic. Even with the name change it is still the same product (and part number #9000) as the previous Supreme 9000.
SynShield™ #700 Durability Advantage, #711 OTR Plus and #722 Ultra Performance oils meet and exceed the Ford WSS-M2C171-E and WSS-M2C171-F1 and are approved by Ford. All Schaeffer’s SynShield® engine oils all meet and exceed API CK-4, CJ-4, CI-4, CI-4 Plus and older.