Upshifts are made by governor pressure and modified by modulator pressure. Which statement describes this correctly?

Upshifts are made by governor pressure and modified by modulator pressure. Which statement describes this correctly?

• A. Upshifts Are Made by Governor Pressure and Modified by Modulator Pressure
• B. Upshifts Are Made by Modulator Pressure and Modified by Governor Pressure
• C. Upshifts Are Controlled by Shift Signal Valves
• D. Upshifts Are Controlled by Pressure Regulator Valve Only

Answer: (A)

In this hydraulic shift system, the upshift signal comes from governor pressure, which increases with engine speed. That governor pressure is then adjusted by modulator pressure to fine‑tune when the shift happens based on engine load and throttle position. So the upshift is driven by governor pressure and tweaked by modulator pressure to ensure a smooth, appropriate shift under different driving conditions. The other ideas aren’t quite right because the governor is the primary trigger for shifting, while modulator pressure simply modifies that trigger to adapt to load. Shift signal valves are part of the overall hydraulic control but don’t initiate the shift by themselves, and the system isn’t governed by a pressure regulator valve alone.

In this hydraulic shift system, the upshift signal comes from governor pressure, which increases with engine speed. That governor pressure is then adjusted by modulator pressure to fine‑tune when the shift happens based on engine load and throttle position. So the upshift is driven by governor pressure and tweaked by modulator pressure to ensure a smooth, appropriate shift under different driving conditions.

The other ideas aren’t quite right because the governor is the primary trigger for shifting, while modulator pressure simply modifies that trigger to adapt to load. Shift signal valves are part of the overall hydraulic control but don’t initiate the shift by themselves, and the system isn’t governed by a pressure regulator valve alone.