From the Warren website their HD30 is listed as a PCMO : Warren 30HD Passenger Car Single Grade Motor Oil (PCMO) is formulated to provide engine protection under severe operating conditions. Made from selected and highly refined base oils compounded to provide protection against wear and corrosion, prevent oxidative thickening and inhibit promotion of engine acids, sludge and varnish deposits. Recommended for all major automotive gasoline and LPG powered engines for passenger cars, pickup trucks and vans. Meets current API licensing Service Category SL, as well as former API Classifications SJ. Warren 30HD is especially recommended for use in automotive applications involving high temperature and heavy duty type service such as hauling boats and camping trailers at sustained high speeds for long periods of time. In all cases, the car or engine manufacturer's lubricant recommendations for API performance category and SAE viscosity grade should be followed." I was looking at the Walmart super tech HD30 SL/SJ rated and was led to beleive it was a HDEO ?