Cool-X Testing

Cool-X has been extensively tested.

Cool-X has been road tested for over 1 million miles in heavy duty trucks, and in hundreds if not thousands of cars. It has also been tested by tribology labs, engine builders, and OEM manufacturers of gearboxes and transmissions. You can understand that much of this testing was done under confidentiality agreements, so there are limits on what we can disclose in detail.

Read Here to Find Out How:


Class 8 Tractor Trailers Show 5% Increase in Fuel Economy with Cool-X in 2 million mile trial

Summary: A national freight carrier conducted a trial of the Cool-X nanotechnology in a Saf-T-Kleen 15W/40 recycled oil  in comparison with Royal Purple synthetic  and Shell Rotella (baseline) for over a year. The trial was conducted on 26 trucks, including 11 with Cool-X, which drove over 2 million miles. All the tractors pulled tankers with the same load over the same route every day with largely the same drivers. The Cool-X / Saf-T-Kleen oil improved the fuel economy over time to 5.5% better than Shell Rotella and 4.2% higher than the Royal Purple synthetic oil. The Cool-X trucks also drove on average about 100,000 miles before a full oil change was required.


The Trial Design:

Vehicles: 26  low mileage Class 8 tractors were part of the study. They used 4 different engines: Detroit Diesel (15), Mercedes Benz (7), Cummins (3) and Volvo (1). Most of the vehicles had been broken in with 20K-30K miles – enough to determine a baseline fuel economy average with Shell Rotella. 11 tractors ran with Cool-X, 16 with Royal Purple (one ran RP first and then Cool-X).

Route, Load: These vehicles were located in one of two depots near a bottled water bottling facility. Every day the trailers would drive 350 miles round trip  to the water source, pick up a tanker load of water, and bring it back to the bottling facility. These tractor trailers drove the same route, with the same load, at the same time each day, encountering similar traffic, for over a year. For the most part, the same drivers drove the same vehicle each day. All 26 trucks in the study were likely to encounter the same weather, traffic, and road conditions as the next truck. As an A to B comparison (between Royal Purple and Cool-X), this test design eliminates most of the variability that typically plagues fuel economy studies.

Maintenance:  These vehicles were well maintained throughout the study. The company practice had been to change the oil (Shell Rotella) every 30K miles with a filter change. The trucks were inspected every 2 or 3 weeks, recording fuel consumption and mileage, testing the oil condition, and topping off the oil as needed. Filters were changed every 30K miles during the study, which necessitated the addition of an additional gallon or so of motor oil. One vehicle with Cool-X had mechanical issues unrelated to the trial that forced it to drop out of the study. Otherwise, the vehicles were driven with Cool-X until they needed an oil change.  The study was terminated after Cool-X vehicles had driven over 800K miles. The Royal Purple trucks were driven 1380K miles, an average of 86K miles per vehicle, during the study period.

Results – Oil Life:  The study was designed initially to evaluate whether a synthetic oil (Royal Purple) would improve oil life and fuel economy sufficiently to warrant the additional expense for the fleet. The test was expanded to include the Cool-X oil as an alternative. The Royal Purple synthetic oil did extend oil life significantly – 5 of 16 vehicles did not need an oil change and averaged 92K miles at the end of the test, and overall the vehicles averaged 48K miles between oil changes.  The Saf-T-Kleen oil with Cool-X added achieved even more astounding results. 8 of the 10 vehicles (leaving aside the one vehicle with mechanical issues) did not require an oil change during the test period; the two that did had the oil change after 105K and 107K miles respectively. Our understanding is that none of the vehicles required an oil change before 100K miles, even after the trial’s data collection period was over; one vehicle finally had a full oil change after over two years of driving. It was also reported that the engines with Cool-X were topped off with substantially less oil than the Royal Purple engines or in comparison with past experience with Shell Rotella (<0.5 quarts per month).

Results – Fuel Economy: As might be expected, the Royal Purple oil improved the fuel economy of the 16 trucks by an average of 1.6%, representing substantial fuel savings of over $800 per truck. The cost of the oil was about the same (higher price, changed less often.

The 11 trucks with Cool-X improved average fuel economy by the end of the study by 5.5%, when compared with Shell Rotella, and by 4.2% compared with Royal Purple, among the 8 trucks that drove more than 42K miles. This represents potential fuel savings of over $3000 per truck per year, although not all of the savings would be realized in the first year – the burnishing process that underlies how Cool-X works takes time – with these engines typically 40K- 50K miles, for the full fuel savings effect to be realized, or roughly 6 months of driving during this trial.

Estimated Savings (2)

Conclusion: Cool-X represents a major opportunity for Class 8 HD Truck fleets to save money on fuel and oil consumption, as well as maintenance costs. A single bottle of Cool-X, bought for <$200, should save a fleet operator over $10,000 in fuel costs alone. Oil costs will probably be cut in half, even after the cost of the Cool-X additive. These savings also omit the benefits of lower maintenance costs, less time in the shop and more in the road, and the likelihood that the reduced wear and oil temperatures will extend not only oil life, but also engine life and reduce repair costs.

Click to see the tables for the raw data.

The first table shows the data for all 26 trucks (beginning miles, miles driven, fuel consumed, mpg, oil and filter changes).

The second and third tables are a detailed look at Vehicle 271299, which was tested for two years; the first with Royal Purple and then subsequently with Cool-X. Worth noting is how Cool-X gradually improves fuel economy consistently throughout the year of the test. This reflects the gradual burnishing process that reduces friction in the engine. After about six months, and 40-50K miles, the fuel economy plateaus. This has been a consistent trend in large diesel engines. The Cool-X continues to deliver lower engine temperatures and longer oil life, but there is a limit to how much fuel economy can be improved.

Cool-X Is Looking To Conduct Additional Fleet Trials in 2013.

Cool-X will provide free product to fleets that have (1) good existing records of fuel economy, e.g., from fleet cards and (2) have at least 20 vehicles with similar configurations, that drive similar routes with similar loads on a daily basis, so we can do a proper random trial with at least 10 vehicles using Cool-X and 10 vehicles as a control. Contact us for more information.


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