System For Selecting A Transmission Economy-Based Shift Schedule

A system for selecting an economy mode shift schedule for a motor vehicle, comprising:

• a transmission having a torque converter and a plurality of selectable gear ranges;
• a transmission control circuit including a control module having the economy mode shift schedule stored therein, the transmission control circuit configured to operably control the transmission;
• an engine control circuit configured to control operation of an engine, the engine being operably coupled to the transmission;
• a communication link configured to transfer information between the transmission control circuit and the engine control circuit;
• wherein, the control module further includes instructions stored therein for executably controlling the transmission control circuit to
• receive engine torque data from the communication link,
• calculate vehicle acceleration,
• determine an accelerator pedal position,
• determine a mode of the torque converter,
• compute a net tractive effort force of the vehicle,
• compare the vehicle acceleration to a first threshold, the accelerator pedal to a second threshold, and the net tractive effort force to a third threshold,
• select the economy mode shift schedule for the transmission based on the comparison;
• and
• control shifting between gear ranges of the transmission according to the economy mode shift schedule.

A method of operating a motor vehicle at an optimal vehicle speed without negatively affecting vehicle productivity, the vehicle having an engine coupled to a transmission, comprising:

• (a) determining gear ratios of all gear ranges of the transmission;
• (b) receiving engine torque data as a function of engine speed for all gear ranges;
• (c) calculating vehicle acceleration and determining accelerator pedal position;
• (d) determining a net tractive effort force of the vehicle for a current gear range of the transmission;
• (e) comparing the vehicle acceleration to a first threshold, the accelerator pedal position to a second threshold, and the net tractive effort force to a third threshold;
• (f) selecting an economy mode shift schedule for the transmission based on the comparison;
• and
• (g) controlling shifting between one or more gear ranges of the transmission according to the economy mode shift schedule.

A method of selecting an economy mode shift schedule for a transmission having X selectable gear ranges and coupled to a powered vehicle, the transmission having a transmission control circuit and the vehicle having an engine control circuit for controlling an engine, comprising:

• calculating vehicle acceleration and a change in accelerator pedal position;
• computing a net tractive effort force of the vehicle for a current gear range N of the transmission, where N<X;
• determining a maximum tractive effort force for all upshift gear ranges, the upshift gear ranges comprising gear ranges N+1, N+2, . . . , and N+J, where J=X−N;
• comparing the net tractive effort force to each maximum tractive effort force;
• and
• selecting the economy mode shift schedule for the transmission based on the comparison.