EVALUATION OF RETARDERS FOR TRANSIT BUSES

The increased weight, higher speeds and use of softer brake-lining materials have resulted in Advanced Design buses (ADSs) achieving lower brake-lining life than the earlier New Look Buses. A vehicle retarder, when actuated, provides an auxiliary and independent braking system for absorbing a portion of the kinetic energy of a decelerating bus. By sharing braking with the service brake system, the retarder results in cooler brakes and increased lining life. Michigan DOT tested 3 types of retarders (engine brake, hydraulic and electric) on buses of the transit systems in Detroit, Grand Rapids and Lansing where they were operated on equivalent routes with buses not so equipped. Measurement of lining life and data on maintenance were compiled. It was show that the engine brake retarder increased brake lining life by up to 1.65 times and the hydraulic and electric retarders achieved 4 to 6 times better lining life. Assuming a 12-year bus life, retrofits would provide net savings of $19,000 to $40,000 per bus. Availability would also be increased. Retarders are adaptable to the ADBs and do provide substantial brake maintenance savings.

• Corporate Authors:

  Michigan Department of Transportation

  Bureau of Urban and Public Transportation, P.O. Box 30050
  Lansing, MI  United States  48909

  Urban Mass Transportation Administration

  Office of Technical Assistance & Safety, 400 7th Street, SW
  Washington, DC  United States  20590
• Authors:
  • Boctor, K
• Publication Date: 1983-6

Media Info

• Features: Figures; Tables;
• Pagination: v.p.

Subject/Index Terms

• TRT Terms: Brake linings; Braking performance; Buses; Energy absorption; Life cycle analysis; Life cycle costing; Maintenance management; Retarders (Concrete); Supply; Vehicle design
• Uncontrolled Terms: Availability; Maintenance costs
• Old TRIS Terms: Bus design; Retarders
• Subject Areas: Design; Finance; Highways; Public Transportation; Vehicles and Equipment; I91: Vehicle Design and Safety;

Filing Info

• Accession Number: 00380184
• Record Type: Publication
• Report/Paper Numbers: UMTA-MI-06-0025-83-1Intrm Rpt.
• Files: TRIS, USDOT, STATEDOT
• Created Date: Dec 30 1983 12:00AM