A new study conducted by Volvo Trucks and Michelin over in Europe claims that using the wrong tires and having improper wheel alignment can increase carbon dioxide emissions by as much as 14.5%.
The study was conducted using two Volvo FH 4x2 trucks, each equipped with a 500 hp., 13-litre Euro 5 engine, and hauling a fully loaded trailer. The rigs each weighed 40 tons. One rig was driven with a variety of incorrect wheel alignment settings while the other used optimally aligned wheels and with standard tractor and trailer tires supplied by Michelin.
“All the conditions tested were realistic, no exaggerations were allowed,” said Arne-Helge Andreassen, business area manager for tyres and wheel alignment at Volvo Trucks’ Aftermarket Department. “Real life is bad enough. Diesel consumption increases dramatically if the wheels are not entirely parallel. And this applies to all vehicles, for construction and long-haul operations too. A trailer with a rear axle angled to the right will roll diagonally across the road and its side panels will operate as a sail that traps the wind.”
The test truck was also run with various tyres and various tyre pressures. The testing was reviewed by Mats Lidbeck from the Technical Research Institute of Sweden, who served as an independent auditor of the testing.
The companies found several interesting facts, not the least of which is that using the correct tire can cut fuel consumption 11% with correct tire inflation reducing it another 1%.
“One-third of fuel consumption stems from the tires’ rolling resistance,” said Jacques de Giancomoni, technical account manager at Michelin. “Having the right tires is of paramount importance. And checking tire pressure - which has a significant effect on fuel consumption - is also important.”