In an Allison transmission, which valve component has cams adjustable to change shift points?

In an Allison transmission, which valve component has cams adjustable to change shift points?

• A. selector
• B. shift signal
• C. shift relay
• D. governor

Answer: (B)

Shift points in an Allison transmission are set by the governor. The governor is a mechanical-hydraulic device that uses weights and a cam profile to regulate governor pressure as engine speed increases. The cams inside the governor are adjustable, which changes the pressure at which the valve body initiates a shift. By altering the cam shape or the spring tension associated with it, you can raise or lower the speed at which the transmission shifts gears. The other components mainly handle input or control signals rather than dictating shift points through cam profiles. The selector is simply the driver input for choosing gears; the shift signal and shift relay are parts of the control logic that pass or act on shift commands, not the cam-driven mechanism that sets when those shifts happen.

Shift points in an Allison transmission are set by the governor. The governor is a mechanical-hydraulic device that uses weights and a cam profile to regulate governor pressure as engine speed increases. The cams inside the governor are adjustable, which changes the pressure at which the valve body initiates a shift. By altering the cam shape or the spring tension associated with it, you can raise or lower the speed at which the transmission shifts gears.

The other components mainly handle input or control signals rather than dictating shift points through cam profiles. The selector is simply the driver input for choosing gears; the shift signal and shift relay are parts of the control logic that pass or act on shift commands, not the cam-driven mechanism that sets when those shifts happen.