ORLANDO, Fla. – International presented aerodynamic test results at the American Trucking Associations annual management conference which the company says disproves Freightliner’s recent claim that its Cascadia is more aerodynamic than the ProStar.

Freightliner raised some eyebrows at International headquarters when it issued a release stating independent wind tunnel testing showed the Cascadia tractor demonstrated 7.8% less drag than the ProStar when tested by Auto Research Center at Freightliner’s Portland wind tunnel. International immediately called into question those results, pointing out the testing did not involve a full-sized trailer.

At the American Trucking Associations annual management conference, International revealed the results of a recent road test to SAE Type III standards.

The test, conducted Oct. 2-3 at a third-party proving grounds in San Angelo, Texas, pitted two ProStars against two comparably spec’d Cascadias, the company reported. The trucks were subjected to six runs, 41 miles in length. GPS technology was used to confirm vehicle speeds of 65 mph and fuel tanks were weighed before and after each run. The drivers and trailers were swapped between vehicles and the results were averaged out. International officials said the result showed a 5.7% average fuel economy improvement for the ProStar over the Cascadia.

The company pointed out a 5.7% fuel economy improvement translates to a savings of about US$3,900 per truck each year.

“As promised, we’ve sought independent, unbiased testing procedures to arrive at this claim,” said Steve Gilligan, assistant general manager, Heavy Vehicle Center, International Truck. “SAE testing procedures are the industry standard. The International ProStar is proven to be more fuel efficient than the Cascadia and a nearly $4,000 annual fuel savings per truck is extremely significant in today’s challenging financial climate for North American trucking companies.”

Mike Hood, development engineer, mileage team at the Goodyear Proving Grounds added “People come here for testing because we can give them unbiased data. We have no interest either way.”

International has contended its ProStar is more aerodynamic than any other Class 8 truck on the market. The recent test results validate that claim, said Bob Weber, chief heavy truck engineer, International.

Of note, however, is that the Freightliner Cascadia tested at the San Angelo proving grounds was powered by a Detroit Diesel engine that had 55 more horsepower than the Cummins ISX (455 hp vs 400 hp). Full results are available at www.internationaltrucks.com.