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Drive Range-First Gear

Drive Range - First Gear:






DRIVE RANGE-FIRST GEAR

CONVERTER CLUTCH - RELEASED
INPUT CLUTCH - APPLIED
INPUT SPRAG - HOLDING
1-2 BAND - APPLIED

When the selector lever is moved to the Drive D position, the manual valve directs line pressure into the Drive D (D4) passage. Drive 4 oil flows to the following:

2-3 Shift Valve: Feeds line pressure through the orifices at the 1-2 servo control valve and check ball #12 to the 1-2 servo. The 1-2 servo applies the 1-2 band.

Governor: Governor pressure increases with vehicle speed. The governor signal pressure pushes against the 1-2, 2-3 and 3-4 throttle valve springs to upshift the transaxle when sufficient vehicle speed is attained.

1-2 Shift Valve: Drive 4 oil at the 1-2 shift valve is the feed oil for the second clutch when the transaxle makes a 1-2 shift.

1-2 Accumulator Valve: 1-2 Accumulator oil pressure is controlled by modulator pressure. Accumulator pressure at the 1-2 and 3-4 accumulator pistons controls the 1-2 and 3-4 shift feel.

SUMMARY
The converter clutch is released; the input clutch is driving the input sprag; the input sprag is driving the input sun gear and the 1-2 band is holding the reaction sun gear.