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There are four direct controls, which affect vehicle behavior: the accelerator pedal, steering wheel, brake pedal and the clutch pedal. Of the four, the accelerator pedal has the most direct influence on the acceleration response of the powertrain. It is the link between the customer's expectations and the powertrain's ability to deliver the expected acceleration. Three main factors are used to evaluate the performance of the accelerator system: force needed to move the pedal, foot travel and foot scrub along the accelerator pedal surface. This paper discusses the design of a new machine, which will provide accurate measurements of the three accelerator system factors.

Increased concerns with fuel mileage in today's vehicles have focused attention on component efficiencies. Even though modern manual transmissions have high efficiencies, these efficiencies can vary widely from manufacturer to manufacturer. This paper addresses these variations and proposes a method for comparing transmissions based on duty cycles and gear usage breakdowns. Also, several approaches are given to address fuel mileage improvements for vehicles with manual transmissions.

This paper presents a discussion on manual transmission torque losses and focuses specifically on the relationship between torque loss, input speed and torque. It also includes a discussion on other factors affecting torque loss, such as inclination angle and lube oil temperature. Manual transmissions used in compact light truck applications have torque losses that are a function of input speed and torque. Efficiency studies done on manual transmissions in the engine-driving mode indicate that torque losses, in other than direct-drive gears, are considerably more dependent on input torque than input speed. It was also observed that efficiency was significantly affected by the inclination angle and lube oil temperature.

This paper discusses the application of advanced coastdown test and analysis methods used to differentiate aerodynamic drag, rolling resistance, and mechanical loss characteristics of light trucks and travel-trailer combinations as related to various light truck classes.

This paper presents a general discussion of automatic transmission parasitic losses and efficiency characteristics. Efficiency characteristics of the three major automatic transmission components-pump, torque converter, and gearbox-and their contribution to the transmission total torque losses are examined. A data reduction method for isolating gearbox torque losses from total transmission losses is also described. The information presented is based on pump, torque converter, and transmission testing performed at SwRI for Ford Motor Company. Test data was used to perform analytical fuel economy benchmarking studies. Testing included 13 transmissions manufactured by American, European, and Japanese manufacturers for 3.0-5.8L truck applications.