Engine oil effects on vehicle fuel economy. Fuel economy improvements in EPA and Road tests with engine oil and Rear Axle Lubricant Viscosity Reduction.

Goodwin, Malcolm C. Haviland, Merrill L.
Society of Automotive Engineers.

1982

1013
CIENA

0-89883-115-6

Effects of reducing engine oil and rear axle lubricant viscosities on fuel economy were determined in EPA combined City and Highway (EPA 55/45) tests and in road tests, usinf four different sized cars. In EPA 55/45 tests, fuel economy rating improvements averaged about 1.5 percent; warned-up and cold-start road test fuel economy improvements averaged about 4 and 8 percent, respectively. For a specific engine oil viscosity reduction, warned-up road test fuel economy increased with decreasing car mass and power-to-mass ratio. Warned-up constant-speed fuel economy improvements obtained by lowering only the engine oil viscosity were about the same as those estimated from reductions in engine friction power. However, measured fuel economy improvents with low-viscosity rear axle lubricants were inexplicably higher than those estimated. Although fuel economy results with low-viscosity lubricants were generally favorable, care must be taken to make sure the use of such lubricants will not reduce vehicle performance and durability under a variety of operating conditions. According, vehicle test are underway. ABSTRACT. PROCEDURES. RESULTS. EPA TESTS. Road Tests. ESTIMATES OF LUBRICANT VISCOSITY EFFECTS ON STEADY-STATE FUEL ECONOMY. DISCUSSION. SUMMARY. CONCLUSION. ACKNOWLEDGMENTS. REFERENCES.

Presenta tbls., y gráfs.

GENERAL; LUBRICANTES; PRUEBAS; VEHICULOS AUTOMOTORES; MOTORES DE GASOLINA; AHORRO DE COMBUSTIBLE; VEHICULOS AUTOMOTORES; USO RACIONAL DE LA ENERGIA; EFICIENCIA ENERGETICA; MOTORES DE COMBUSTION;