Q: How do I know if re-refined oils are okay to use in my engines?
A: Check with your engine manufacturer for the specific recommendation on which engine oil to use. That said, all major OEMs have approved EcoPower Heavy Duty Diesel Engine Oil in 15W-40 CJ-4 and 10W-30 CJ-4, as well as many other re-refined oils. EcoPower also meets or exceeds the toughest North American standards for engine protection, including the Society of Automotive Engineers (SAE), the American Petroleum Institute (API) and the International Lubricant Standards Advisory Committee (ILSAC).
Information provided by: Safety-Kleen / EcoPower