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Drive Range - First Gear

Drive Range - First Gear:






DRIVE RANGE-FIRST GEAR

FORWARD CLUTCH - APPLIED
LO ROLLER CLUTCH - HOLDING

When the selector lever is moved to the Drive position, the manual valve is repositioned to allow line pressure to enter the Drive circuit.
1. Forward Clutch
2. 1-2 Shift Valve
3. Governor Assembly
4. Rear Accumulator
5. Detent Regulator Valve

BASIC CONTROL

Drive oil is directed to the forward clutch were it acts on two areas of the clutch piston to apply the forward clutch. The inner area is fed through an unrestricted passage. The outer area is fed through an orifice to ensure a smooth shift from Park, Neutral, and Reverse to Drive.

Drive oil at the governor assembly is regulated to a variable pressure called governor pressure. Governor pressure increases with vehicle speed and acts against the ends of the 1-2, 2-3 shift valves, and the modulator valve.

Drive oil at the rear accumulator is orificed to a pressure called 1-2 accumulator pressure 1-2 accumulator oil works against modulator oil at the 1-2 accumulator valve.

SUMMARY

The converter is filled. The forward clutch is applied. The transmission is in Drive Range - First Gear.