FLEET MANAGEMENT/Miami-Dade system keeps oil running longer

For most government fleets, the every-5,000-mile oil change is a fact of life. In Miami-Dade, however, the jurisdiction’s school buses have not had an oil change since 1994. That means less down time for the buses, less money spent for oil and less of a need to dispose of used oil. Surprisingly, it does not mean engine damage.

The school buses provided the test case for an on-board bypass filtration system, manufactured by Boca Raton, Fla.-based Puradyn, that cleans and maintains engine oil for thousands of miles. In fact, some of the Miami-Dade school buses have gone more than 130,000 miles without an oil change. In 1999 alone, the system saved the local government nearly $175,000 on new oil purchases, disposal costs and downtime.

The system was screened by the Miami-Dade Efficiency and Competition Commission, which checks out products and services that could make the government work better. “We get a lot of ideas,” says Miami-Dade Mayor Alex Penelas. “Some of them work, and some of them don’t pan out very well. This one worked.”

The system removes soot and contaminants as small as .25 microns, cleaning the oil and allowing it to maintain its intended viscosity. (Standard oil filters remove contaminants in the 15- to 40-micron range.) The system works in conjunction with conventional filtration systems.

Miami-Dade, which operates the third largest school district in Florida, has purchased another 270 school buses, all of which will be equipped with the system, according to School District Transportation Director Thomas Harrison. Additionally, the local government is installing the system in its police and maintenance vehicle fleets, and Penelas predicts that eventually every vehicle in the Miami-Dade fleet will be equipped with it. “It is saving us a lot of money,” he says.

The environmental savings also are key in ecologically sensitive South Florida. Legal disposal of used oil is expensive, so millions of gallons every year are disposed of illegally. One gallon of oil that is improperly discarded can contaminate a million gallons of drinking water. In 1995, the American Oceans Campaign endorsed the on-board bypass filtration system as having “enormous pollution prevention and energy conservation potential.”