Safety-Kleen Systems, which markets EcoPower re-refined engine oil, announced on July 25 the results of a four-year, million-mile test of the engine oil used in two 2007 Cummins ISX 450 HP EGR diesel engines operated by Cooke Trucking Co.

The test engines powered two Peterbilt 387 over-the-road (OTR) conventional trucks used in long-haul service, primarily hauling furniture to the West Coast and backhauling reefer trailers. Cooke Trucking operates a fleet of 50 trucks and is headquartered in Mt. Airy, N.C.

This was the first-ever official million-mile engine test of re-refined oil in actual fleet service. Testing was completed in July 2012. A special media event held at Outcast Kustoms, a truck customizing company headquartered in Mooresville, N.C., included a teardown of the two Cummins ISX diesel engines using EcoPower re-refined oil.

Testing Performance

The test aimed to evaluate how well HD15W-40 CJ-4/SM oil protected engine components during 1 million miles of fleet service. The test was conducted by Infineum, an independent third-party company, which is a joint venture created by ExxonMobil and Shell Oil in 1999. Infineum’s primary business is manufacturing petroleum additives for lubricants and fuels. Technicians from Cummins Inc. also assisted in the engine teardown.

Infineum has used Cooke Trucking as a test fleet since 1988. Although drivers and technicians at Cooke Trucking knew they were testing engine oil, the actual oil being tested was not disclosed to them or the Infineum employees administering the test, and there was no product identification on the test oil containers. The purpose of the test was to show how re-refined engine oil performed against oil produced from original petroleum base stock.

Demonstrating the results of the million-mile engine teardown was Pat Fetterman, industry liaison advisor for Infineum, who said the engines “look like what I would expect to see with premium oil at 1 million miles.”

All test engine components showed normal wear.

The first 500,000 miles of the test involved comparison testing against premium oils from two leading brands of engine oil. According to Infineum, the used-oil analysis showed EcoPower outperformed the leading competitive oils in total base number retention and viscosity.

The million-mile test targeted a 40,000-mile drain interval, with most drains occurring between 40,000 and 50,000 miles. The trucks averaged 6.2 mpg over their duty cycles. 

A Look at Safety-Kleen’s Oil Re-Refining Process

In 2008, Plano, Texas-based Safety Kleen began marketing re-refined oil to corporate fleets and its existing customer base of public sector and military fleets. Safety-Kleen collects 200 million gallons of used oil from 115,000 locations and re-refines approximately 160 million gallons annually. 

The collected used oil is put through a closed-loop refining process, which includes vacuum distillation and hydro-treating. This process removes contaminants, such as fuel, water, sulfur, and dirt from the used oil and leaves a new base oil, which Safety-Kleen said is better than the base oil made from crude. After being re-refined, the base oil is blended with a package of additives to help reduce oxidation and engine wear and protect against viscosity and thermal breakdown.

EcoPower's re-refined engine oil has been approved by several diesel engine manufacturers, such as Caterpillar, Cummins, Mack, Detroit Diesel, and Mercedes-Benz. EcoPower is available in the following grades: 15W-40 CJ-4/SM, 10W-30 CJ-4/SM, and NGP-2 15W-40 natural gas engine oil.