Pneumatic control with pre-exhaust for range section of transmission.

摘要

A fluid pressure actuated auxiliary transmission section (14) shift control system (230)/method is provided which includes control members to minimize the possibility of auxiliary section synchronized clutch (92, 128) damage by the main transmission section (12) being engaged during an auxiliary section shift. A range interlock assembly (258) is provided which will release the range slave valve (238) as the main transmission section is shifted into the neutral position thereof and preexhaust valves (300, 302) are provided which will exhaust the appropriate actuator chamber (222A, 224A) upon preselection of an auxiliary section shift.