Field Testing & Analysis of Braking Performance of In-Service Trucks

The National Highway Traffic Safety Administration (NHTSA) is on the verge of requiring that the stopping distance of new trucks be reduced up to 30 percent below current regulations, depending on the vehicle type. However, this regulation does not address the braking performance of trucks after they have entered into service. Further, the current in-service vehicle inspection procedure, as well as the required annual inspection of commercial motor vehicles (CMVs), may be missing a critical component of braking capability, that of the effectiveness of after-market or replacement brake linings, which have a direct impact on stopping capability. Inspection procedures for CMVs cannot assess the friction available at the pad versus drum (or disc) interface, and there are no data available on the criticality to safety of this aspect of the inspection process. The objective of this project is to obtain a data set of the stopping capability of in-service CMVs. This will be accomplished through the performance-controlled stopping distance and deceleration tests and performance-based brake tests of in-service heavy trucks. The data set will provide a current assessment of the distribution of the braking capabilities and performance required of in-service vehicles that can be compared with that of new vehicles. These stopping performance tests will be complemented by visual inspections of the brake system by qualified inspectors. Federal Motor Carrier Safety Administration (FMCSA) and NHTSA need these data for assessing the effectiveness of current safety standards and regulations, and to support changes to such standards and regulations, including those covering replacement brake linings. Industry has similar interest in the data to assess the importance of replacement linings and maintenance on fleet safety.

  • Supplemental Notes:
    • This project is funded by National Transportation Research Center Inc. NTRCI-UTC which is a separate entity from the University of Tennessee Regional UTC called the "STC".


  • English


  • Status: Completed
  • Contract Numbers:



  • Sponsor Organizations:

    National Transportation Research Center, Incorporated

    Oak Ridge National Laboratory
    Knoxville, TN  United States  37932
  • Project Managers:

    Petrolino, Joseph

  • Performing Organizations:

    Department of Transportation

    Federal Motor Carrier Safety Administration
    1200 New Jersey Avenue, SE
    Washington, DC    20590

    Heavy Duty Manufacturers Association

    10 Laboratory Drive
    Research Triangle Park, NC  United States  27709

    Commercial Vehicle Safety Alliance

    1101 17th Street, NW
    Suite 803
    Washington, DC  United States  20036

    Ontario Trucking Association

    555 Dixon Road
    Toronto, Ontario    M9W 1H8

    Battelle Memorial Institute

    Columbus Laboratories
    Columbus, OH  United States  43201
  • Principal Investigators:

    Shaffer, Steven

  • Start Date: 20080301
  • Expected Completion Date: 0
  • Actual Completion Date: 20090228
  • Source Data: RiP Project 17656

Subject/Index Terms

Filing Info

  • Accession Number: 01464503
  • Record Type: Research project
  • Source Agency: National Transportation Research Center, Incorporated
  • Contract Numbers: DTRT-06-G-0043-01, DTRT-06-G-0043-01-U1
  • Files: UTC, RiP, USDOT
  • Created Date: Jan 3 2013 2:43PM