Hitachi ZW180 Technical Manual page 322

Forward 1st Speed
In case of forward 1st speed, the forward clutch is
connected to the 1st speed part of the 1st / 2nd
speed clutch. The torque converter transmits torque
to F hub gear (4) which is meshed with input gear (1).
Torque from F hub gear (4) is transmitted to 1st
speed hub gear (10) through F-R gear (3), idler gear
(7) and idler gear (8).
10
11
COMPONENT OPERATION / Drive Unit
1
4
Forward
Clutch
3
7
1st / 2nd
Speed
Clutch
16
Power Flow: Forward 1st Speed
In addition, torque is transmitted from 1st hub gear
(10) to low-range gear (11), and finally to output gear
(16).
Input
8
Output
T3-9-16
T4GC-03-09-015