GMC 4000 Series Service Manual page 148

ASSEMBLY (Fig. 24)
1. Install washer, long spacer, spring, washer,
short spacer, and nut on push rod.
2. Tighten adjusting nut until dimension over
washers at each end is 2-27/32" (fig. 25). Install
and tighten lock nut, being careful not to change
dimension.
3. Lubricate inside of piston rod then install
push rod and spring assembly.
4. Compress push rod spring and install snap
ring.
5. Install push rod assembly in housing.
6. Install new diaphragm and plates to push
rod and tighten nut securely.
NOTE: Apply sealing compound around push
rod hole in diaphragm plates.
7. Install outer half of cylinder to inner half
and secure with screws tightened securely.
8. Attach assembly to differential carrier,
using new gasket. Tighten cap screws securely.
9. Attach hoses to cylinder, being sure con­
nections are tight.
1 Diaphragm
2 Shift Chamber Assembly
3 Oil Seal
4 Differential Carrier
5 Push Rod Spring
6 Push Rod
7 Piston Rod
Figure 2 6 — Sectional V ie w of Tw o-Speed A xle Shift C ham ber Installation (Rockwell)
G M C S E R V I C E M A N U A L
SHIFT CHAMBER (ROCKWELL AXLE)
REMOVAL AND DISASSEMBLY (Fig. 26)
hose from chamber. Tag each hose so that it can
be identified and installed in proper position.
8 Lock Screw and Nut
9 Shift Fork
10 Sliding Clutch
11 Clutch Poppet
12 High Speed Gear
13 Cross Shaft
REAR AXLE A N D CONTROLS
Figure 2 5 — Adjusting Push Rod (Corporation)
1. Remove hose clamps, then remove vacuum
14 Low Speed Gear
15 Mounting Sleeve
16 Adjusting Shims
17 Stud and Nut
18 Snap Ring
19 Nut
Sec. 4A
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