In-Service Analysis of Maintenance and Repair Expenses for the Anti-Lock Brake System and Underride Guard for Tractors and Trailers

摘要

Federal Motor Vehicle Safety Standards (FMVSS) Nos. 121 and 105 mandate antilock braking systems (ABS) on all air-braked vehicles and hydraulic-braked trucks and buses with a gross vehicle weight rating (GVWR) of 10,000 pounds or greater. The primary purpose of this report is to analyze the maintenance and repair expenses to the ABS systems of tractors and trailers. A contractor assembled a database with a census of repair receipts from 13 trucking fleets during the period of about 2000 to 2003, with over 4,000 vehicles total. The average ABS expenses per month of operation were $0.85 for tractors and $0.25 for trailers (in 2007 dollars), for vehicles classified built after the effective date for ABS implementation. Across a vehicle lifetime, the net present value of the maintenance and repair expenses is estimated to range from $56 to $102 for tractors and from $16 to $30 for trailers. These values are relatively small compared to the cost of equipping new vehicles with ABS systems, estimated as $639 for tractors and $513 for trailers in an earlier NHTSA report. The presence of the ABS system does not appear to increase overall maintenance expenses to the brake system. Older vehicles, manufactured before the effective date for ABS implementation, had higher brake expenses, both per month of service and as a percentage of total maintenance expenses during the survey. The average maintenance and repair expenses to the underride guards, mandated on trailers with a GVWR of 10,000 pounds or greater by FMVSS Nos. 223 and 224, were $0.16 per month of service, representing a net present value of $15 over the vehicles lifetime.