Which hydraulic source applies the transmission's clutches?

Which hydraulic source applies the transmission's clutches?

• A. Main pressure
• B. Modulator pressure
• C. Governor pressure
• D. MPRV pressure

Answer: (A)

Clutch actuation in an automatic transmission is powered by the main hydraulic pressure created by the transmission pump. This main pressure flows through the valve body to the clutch pistons, directly engaging and releasing the clutch packs to select gears. Other pressures play supporting roles: governor pressure provides a speed-based signal for shift timing, modulator pressure helps tailor line pressure for smoother shifts, and the MPRV pressure acts as a relief to protect the system. So the direct source that actually applies the clutches is the main pressure.

Clutch actuation in an automatic transmission is powered by the main hydraulic pressure created by the transmission pump. This main pressure flows through the valve body to the clutch pistons, directly engaging and releasing the clutch packs to select gears. Other pressures play supporting roles: governor pressure provides a speed-based signal for shift timing, modulator pressure helps tailor line pressure for smoother shifts, and the MPRV pressure acts as a relief to protect the system. So the direct source that actually applies the clutches is the main pressure.