All of the transmission's hydraulic circuits are fed by the __________circuit.

• A. Starter solenoid
• B. Main pressure
• C. Lubrication
• D. Modulator

Answer: (B)

The main pressure circuit is the primary feed for hydraulic actuation in a transmission. The pump creates a high-pressure supply that travels through this circuit to the valve body, which distributes pressure to the clutches, bands, and servo pistons that actually shift gears. This centralized main pressure ensures all hydraulic circuits operate with the same controlled pressure. The lubrication circuit, while it carries oil for lubrication and cooling, is separate from the hydraulic actuation pathways. The starter solenoid belongs to the starting system, not to hydraulic transmission circuits. The modulator circuit is a control path that helps adjust line pressure under different operating conditions but does not serve as the universal feed to all hydraulic components.