Hitachi ZW180 Technical Manual page 330

Reverse 1st Speed
In case of reverse 1st speed, the reverse clutch is
connected to the 1st speed part of the 1st / 2nd
speed clutch. The torque converter transmits torque
to R hub gear (6) from reverse gear (2) which is
meshed with input gear (1).
Torque from R hub gear (6) is transmitted to 1st
speed hub gear (10) through F-R gear (5), idler gear
(7) and idler gear (8).
1st / 2nd
Speed Clutch
10
11
16
COMPONENT OPERATION / Drive Unit
1
7
Power Flow: Reverse 1st Speed
In addition, torque is transmitted from 1st speed hub
gear (10) to low-range gear (11), and finally to output
gear (16).
The processes of the idler gear and after for the other
reverse speed shifts are similar to those for the
forward.
Input
8
Output
T3-9-24
2
6
Reverse
Clutch
5
T4GC-03-09-023