API is the only national trade association representing all facets of the natural gas and oil industry, which supports 10.3 million U.S. jobs and nearly 8% of the U.S. economy.

Engine oil is as versatile as it is vital. Not only does it lubricate an engine’s moving parts so there’s no metal-to-metal scuffing, it also disperses heat. Now it performs better than ever. The CJ-4 ...

Among the new tests are a chain-wear evaluation, to assess an oil’s ability to protect the timing chain, and a low-speed-pre-ignition test for oils used in smaller, turbocharged, gasoline engines with ...

The Engine Oil Program runs regular physical, chemical, and performance tests on licensed engine oils and verifies that the API-registered Marks are properly displayed on containers and convey ...

These API engine oil categories, CJ-4 and CK-4, differ in their performance attributes, which contribute to a vehicle’s overall fuel economy and operating capacity.

Equipment Fleet Maintenance Oils, Lubricants & Greases API Approves Development of PC-12 Diesel Engine Oil Category Fleets and drivers should expect improved oil performance, which supports ...

The former would be backward compatible with CJ-4 and its predecessor oils; the latter would initially have limited application, primarily for newer on-highway truck engines. To ensure that the new ...

Engine oil is as versatile as it is vital. Not only does it lubricate an engine’s moving parts so there’s no metal-to-metal scuffing, it also disperses heat. Now it performs better than ever. The CJ-4 ...