AUTOMOTIVE ENGINE FRICTION AND FUEL EFFICIENCY -- VISCOUS VERSUS NON-VISCOUS EFFECTS

The influences on fuel efficiency of viscosity difference and friction modification by colloid friction modifiers in motor oil were examined separately and in combination in a series of automobile track tests using EPA test procedures. The results demonstrated the following: 1. Simply reducing the viscosity of multigrade engine oils did not produce consistent, statistically significant fuel economy benefits. 2. The incorporation of a colloid friction modifier in reduced viscosity multigrade oils produced consistent and statistically significant improvements in fuel economy over those same reduced viscosity multigrade oils without colloid friction modification. 3. Whereas reduced viscosity multigrade oils did not show significant benefits over a commercial type SAE 10W-40 proposal S-1 oil, those same reduced viscosity multigrade oils containing colloid friction modifier demonstrated consistent and statistically significant improvements in fuel economy over that commercial oil. 4. Incorporation of colloid friction modifier in a single grade (SAE 30) oil produced consistent and statistically significant improvements in fuel economy over the commercial type SAE 10W-40 oil. Statistically valid improvements in fuel efficiency due to the presence of colloid friction modifier can be observed in this data in the general range of five to ten percent. Paper No. 780984.

  • Supplemental Notes:
    • From SAE Special Publication 434 (Relation Between Engine Oil Viscosity and Engine Performance, Part 4). Paper presented at the SAE International Fuels and Lubricates Meeting, Toronto, Ontario, 13-16 November 1978.
  • Corporate Authors:

    Society of Automotive Engineers (SAE)

    400 Commonwealth Drive
    Warrendale, PA  United States  15096
  • Authors:
    • Chirla, P J
    • SMITH, R K
  • Publication Date: 1978

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Subject/Index Terms

Filing Info

  • Accession Number: 00195234
  • Record Type: Publication
  • Source Agency: Engineering Index
  • Report/Paper Numbers: Conf Paper
  • Files: TRIS
  • Created Date: Aug 28 1979 12:00AM