GMC 1976 ZEO 6083 Maintenance Manual page 217

POS . CAMBER POS . CAMBER
VERTICAL VERTICAL
GROUND
TOE-IN . . . . . ..... . .
G = F + .06"
CAMBER . . . . . . . . . . . .
0
0
TO
+ 1/2 0
A-4635
Figure 67-Rear Wheel Alignment Chart
2. Loosen six bolts on mounting bracket.
3. Insert proper shim as shown in Figure 68 .
4. Tighten 4 retaining nuts on frame rail to
65-85 ft . lbs. torque . Tighten two retaining nuts on
crossmember to 50-60 ft . lbs . torque .
5. Lower vehicle to floor and recheck alignment.
Figure 68-Rear Wheel Shim Location
REAR WHEEL CAMBER
REAR SUSPENSION 4- 3 3
The rear wheels are set with positive camber.
Positive camber is outward inclination of wheels at
top.
In checking camber, it is recommended that an
accurate gauge be used . The camber should be set at
0° to + 1/2° (See figure 67).
Excessive positive camber results in irregular
wear of tires at outer shoulder . Negative or reverse
camber causes wear at inner shoulders .
Camber is adjusted by shimming as shown in
Figure 68 . Following the same shimming procedure
as that used before to set toe-in .
AIR COMPRESSOR PRESSURE
SWITCH ADJUSTMENT
The switch is designed to maintain air pressure in
the air reservoir between 100 and 120 psi. If the
pressure in the reservoir drops to 100 psi the contact
points will close and this will complete the circuit
supplying electricity to the compressor . If the pres-
sure raises above 120 psi the contact point will open
the circuit to the compressor . This setting may be
adjusted at the nut which is located on the end of the
spring inside the cover, refer to Figure 69 . The pres-
sure will rise by tightening the spring . Both the cut-in
pressure and the cut-out pressure will be affected by
Figure 69-Air Compressor Pressure Switch
Adjustment