The influence of tire-in-use factors (inflation pressure, replacement mixes, and wear) on the steering and braking response of automobiles is examined through analysis, simulation, laboratory and over-the-road tire testing, and vehicle testing. Results for a 1971 Mustang and a 1973 Buick station wagon illustrate the influence of tire-in-use factors on (a) the open-loop braking and/or turning performance in drastic maneuvers on wet and dry surfaces, and (b) the understeer/oversteer factor for maneuvers involving lateral accelerations below 0.3 g. The investigation shows that differences in tire mechanical properties between the front and rear wheels (as caused by tire-in-use factors) can cause significant and potentially dangerous changes in limit response and from the stability and control characteristics intended by the vehicle manufacturer. The report recommends that (1) inspection limits for inflation pressure be within + or - 1 psi of the manufacturer's recommended level, (2) minimum tread-groove depth exceed 2/32 in., and (3) further research be conducted to develop a cost-effective means for indicating the lateral force characteristics of a tire.

  • Supplemental Notes:
    • See also PB-241 128 and PB-241 129.
  • Corporate Authors:

    University of Michigan, Ann Arbor

    Highway Safety Research Institute
    Ann Arbor, MI  United States 

    National Highway Traffic Safety Administration

    1200 New Jersey Avenue, SE
    Washington, DC  United States  20590
  • Authors:
    • BERNARD, J E
    • Fancher, P S
    • Gupta, R
    • Moncarz, H
    • Segel, L
  • Publication Date: 1975-3

Media Info

  • Pagination: 230 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00151763
  • Record Type: Publication
  • Source Agency: National Technical Information Service
  • Report/Paper Numbers: UM-HSRI-PF-75-1-2, DOT-HS-801-439
  • Contract Numbers: DOT-HS-031-3-693
  • Files: NTIS, USDOT
  • Created Date: Apr 27 2002 12:00AM