​ “The goal of these trials was to identify the real value of each technology so fleet operators can focus their implementation efforts where they get the best value and can more easily justify their capital investment,” said Yves Provencher, Director of PIT. “Our controlled test-track fuel efficiency studies accelerate technology implementation and provide the commercial vehicle industry with the information it needs to make sound technology choices.”

For the fuel economy evaluations, PIT tested side skirts from Freight Wing, Laydon Composites, Ridge Corporation and Transtex Composite. Fuel savings with the devices ranged from 5.2% to 7.45% compared to similar vehicles without skirts.

Trailer undercarriage air deflectors tested by PIT were supplied by AirFlow Deflector, Airman and SmartTruck. Fuel savings measured on vehicles equipped with the devices ranged from 0% to 2.2%.

PIT testing on the trailer aerodynamic devices was performed in accordance with SAE J1321 Fuel Consumption Test Procedure - Type II. For each test, unmodified control vehicles and test vehicles had the same general configuration, were coupled to the same trailers for base and test segments, and maintained load weights the same throughout the entire test period. All vehicles were in good working condition and set to manufacturer’s specifications.

Fuel consumption for the tests was measured by weighing portable tanks before and after each trip. The testing consisted of a baseline segment using non-modified vehicles followed by a segment using the control vehicle and test units equipped with the aerodynamic devices. For baseline and final segments, results were presented as the ratio between the average fuel consumed by the test vehicle and the average fuel consumed by the control vehicle. The values for fuel savings reflect the changes resulting from the modification of test vehicles.