Part Throttle 4-3

Part Throttle 4-3 And Modulated Downshift - Valves Shown In Third Gear Position:

PART THROTTLE 4-3

CONVERTER CLUTCH - APPLIED
SECOND CLUTCH - APPLIED
THIRD CLUTCH - APPLIED
THIRD ROLLER CLUTCH - HOLDING

When the accelerator pedal is depressed far enough, the Throttle Valve (T.V.) plunger feeds T.V. pressure into the part throttle (P.T.) passage.
1. Part throttle pressure pushes the 3-4 shift valve closed, fourth clutch oil exhausts and the fourth clutch releases.
2. In certain situations, 4-3 Modulated Throttle Valve (M.T.V.) oil pressure could shift the transaxle from Fourth to Third Gear. At low vehicle speeds in Fourth Gear, with the accelerator pedal depressed (but not far enough to open the P.T. passage) the 4-3 M.T.V. pressure could downshift the transaxle to Third Gear.

SUMMARY
Part throttle oil shifts the transaxle from Fourth to Third Gear.