Evans Coolants says its unique waterless engine coolant has shown fuel savings of 3 percent to 7 percent in fleet testing.

Year-long results from a test with USA Hauling, a CT refuse fleet, showed fuel savings of 7.2 percent for Evans Heavy Duty Thermal Coolant. The Pioneer Valley Transit Authority in Springfield, Mass., conducted a year-long evaluation on several city buses and found fuel savings of 4.4 percent.

At Veolia Environmental Services in Wisconsin, an ongoing fuel economy test shows a fuel economy improvement of 4.2 percent for the seven-month period through April. Evans spokesman Mike Tourville expects the Veolia results to improve further as ambient temperatures get hotter.

The savings were achieved by resetting fan-on and thermostat temperatures for the high-boiling-point coolant. Increasing fan-on temperatures saves fuel because the fans run less frequently.

The PAVE Research Center at Auburn University conducted an SAE Type II Fuel Consumption Test (J1321) using two Detroit Diesel-powered trucks from its fleet. The test truck was converted to Evans waterless coolant and its thermostats were replaced with thermostats actuating at 215 degrees. To remove the fans from being a variable, the fans of both trucks were locked "on" 100 percent of the time. The test truck achieved a 3.04 percent improvement in fuel economy over the control truck from the higher operating temperature.

While these savings are significant and show a payback for the coolant, Tourville points out that this is an incidental benefit. Because the cooling system never needs draining, runs at a very low pressure and experiences no corrosion, the long-term benefit of Evans cooling is the increased reliability and durability of the equipment and the lower cooling system maintenance costs, he says.

One coolant expert cautions that fleets that opt to use waterless coolant will need to make sure they have tight control of their maintenance practices. "The problem is if you add water to them, you're in a world of hurt because corrosion starts going crazy," says Carmen Ulabarro, direct marketing manager at Chevron Products Co. "When a guy's out on the road, what's the easiest thing to find is water. That is a huge dimensional change."

From the June 2010 issue of Heavy Duty Trucking.