Stopping Distance Analysis of 5 Axle Versus Proposed 6 Axle Tractor Trailers in North America

Many jurisdictions in the U.S. are investigating increasing Gross Vehicle Weight Ratings from 80,000 lbs. GVWR to 91,000 lbs. GVWR with the addition of a third axle to the trailer. The impact on vehicle stopping distance was investigated. Comparison modeling of lighter 5 axle versus heavier 6 axle configurations was performed. Analysis of differences in road surface coefficient of friction, CG height and trailer axle brake torque levels were performed using a custom stopping distance model. This presentation discusses the modeling method, assumptions and the results.