How to Compare Semi Trucksby Richard Rowe
Semi tractor trailer buyers need to consider a number of criteria that the average auto buyer doesn't. Used trucks can have several million miles on the odometer with at least that many left in them, which is a very real factor in the purchasing decision.
Mileage is everything where used tractor trailers are concerned, and is the primary reason that people buy new ones. Different chassis and engines have different known failure mileages, so talk to other drivers with a similar year, make, model and mileage truck to determine what's likely to fail in the near future.
The average truck driver can easily cover 170,000 miles per year, which means that a one-tenth-of-an-mpg deficit can add up to hundreds of dollars at the end of the year. Aerodynamic bodywork is one of the most important factors in truck fuel economy.
Large displacement with a long stroke relative to bore tend to be more efficient at hauling heavy loads in hilly or mountainous terrain; smaller engines with a larger bore and shorter stroke tend to be better around town and while sustaining a constant speed over flat land.
Wheelbase (the distance between the steering axle and front drive axle) is one important consideration where trucks are concerned. A long wheelbase truck rides smoother, is more stable at high speed and can potentially have better aerodynamics if the body is optimized for the wheelbase. A shorter wheelbase truck is far easier to maneuver, and can drive and back into places that a long truck couldn't even approach.
- "Trucking: Tractor-Trailer Driver Handbook/Workbook"; Career Publishing; 2008
- Society of Automotive Engineers: Tractor Trailer Aerodynamics
- Yacht Survey: Comparing Diesel Types
- Cargo Bull: Variable Wheelbase Tractor Trailers
Richard Rowe has been writing professionally since 2007, specializing in automotive topics. He has worked as a tractor-trailer driver and mechanic, a rigger at a fire engine factory and as a race-car driver and builder. Rowe studied engineering, philosophy and American literature at Central Florida Community College.