TRUCK NOISE IV-A: PROJECT SUMMARY - THE REDUCTION OF NOISE LEVELS ON THE INTERNATIONAL HARVESTER QUIETED TRUCK

Truck noise is a complex interaction of many noise sources which can be isolated and studied on an individual basis. Significant reductions in diesel truck noise can be achieved with the current state-of-the-art by using a systematic approach on each major source of noise. Cooling system noise was reduced through a series of modifications which permitted a reduction in fan speed with no sacrifice in cooling ability. Exhaust system noise was reduced by using improved, large volume mufflers and muffler wraps. Intake system noise was reduced by adding a silencer between the air cleaner and the engine together with changing the type of rain cap. Engine noise was reduced by acoustical shielding in the form of either close-fitting covers or a partial enclosure. These modifications were accompanied by increases in weight and length of the truck, along with increases in initial cost and maintenance cost. In the long run, a portion of these cost increases can be recovered by improved fuel economy resulting from lower cooling fan horsepower. Future development efforts should be directed toward improved ways of reducing the engine noise, improved mufflers having reduced weight, methods of reducing pipe shell noise and improved exhaust joints.

  • Supplemental Notes:
    • See also report no. 2 dated May 75, PB-244 270.
  • Corporate Authors:

    International Harvester Company

    Truck Engineering Center
    Fort Wayne, Indiana,   USA  46801

    Office of the Secretary of Transportation

    Office of Noise Abatement, 1200 New Jersey Avenue, SE
    Washington, DC  USA  20590
  • Authors:
    • Shrader, J T
  • Publication Date: 1976-6

Media Info

  • Pagination: 146 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00146485
  • Record Type: Publication
  • Source Agency: National Technical Information Service
  • Report/Paper Numbers: DOT/TST-76-89 Final Rpt.
  • Contract Numbers: DOT-OS-20222
  • Files: TRIS, USDOT
  • Created Date: Feb 16 1977 12:00AM