Chevrolet 10 Series 1970 Service Manual page 222

REAR SUSPENSION AND DRIVE LINE 4-46
AXLE ASSEMBLY
NOTE: A ll axle attachments a re im portant at­
taching parts in that they could a ffect the p e r ­
form ance o f v ita l components
and/or could resu lt in m ajor r e p a ir expense.
They must be replaced with parts o f the same
part numbers o r with equivalent parts i f r e ­
placem ent b ecom es n ecessary. Do not use r e ­
placem ent parts o f le s s e r quality o r substitute
design. Torque values must be used as sp ecified
during rea ssem b ly to assure p rop er retention of
these p arts.
Removal
1. Loosen the r e a r wheel stud nuts, then ra ise the rea r
o f the v e h icle enough to rem ove the load fro m the
re a r springs. Support v e h icle with stand jacks under
fra m e side ra ils .
Disconnect the hydraulic brake hose fro m the brake
2 .
pipe at the re a r axle, o r, if the truck is equipped with
a ir brakes, bleed the system , then disconnect the a ir
brake hose fro m the r e a r brake cham bers.
Rem ove the axle shift unit.
3 .
a. lb. E le c tr ic Shift; rem ove the two stud nuts
1 8 ,5 0 0
retaining r e a r axle e le c tric
unit fro m • d iffe re n tia l c a r r ie r .
e le c tr ic w irin g fro m the shift unit and tape w ire
term in als sep arately.
b. lb. A ir Shift system ; bleed a ir from a ir
2 3 ,0 0 0
system and disconnect a ir line at c o ve r on shift
unit. Rem ove the two stud nuts retaining re a r
axle shift unit and pull unit fro m
c a r r ie r . Tape connections to prevent d irt from
entering system .
4. Rem ove the two trunnion bearing " TP* bolts fro m the
pinion flange and sp lit the re a r universal joint. Swing
the p ro p e lle r shaft to one side and tie it to the fram e
side ra il.
Rem ove the re a r spring " U " bolts and r o ll the axle
5 .
assem bly out from under the truck. R aise the axle
c le a r o f the flo o r and rem ove the w heels.
Installation
1. In stall the w heels, then r o ll the axle assem bly into
position under the truck.
Attach axle to the re a r springs with the " U" bolts.
2 .
Tighten the " U " bolt nuts to specification s.
Connect p ro p e lle r shaft to the axle and torque to
3 .
sp ecification s.
4. Connect w irin g to e le c tr ic shift unit and install shift
unit on c a r r ie r
1 8 ,5 0 0
c a r r ie r and connect a ir line at c o v e r
Connect the hydraulic brake hose to the brake pipe on
5 .
the re a r axle, then bleed the brakes and check fluid
le v e l in m aster cylin d er.
with a ir brakes, connect a ir lin es to the re a r brake
cham bers.
6. L o w e r veh icle to flo o r and tighten re a r wheel nuts.
7. F ill axle and shift unit to p rop er le v e l with lubricant.
8. Check brake operation.
fluid leaks at brake line fittin gs.
A xle Vent
Replacement
See " A x le Vent R ep lacem en t" Eaton Single-Speed A xle.
and system s,
shift unit and pull
Disconnect the
d iffe ren tia l
lb. axle. Install shift unit on
lb. axle.
2 3 ,0 0 0
If the truck is equipped
Inspect fo r a ir o r hydraulic
A xle Shaft
Removal and Installation
See " A xle Shaft—R em oval
Single-Speed A xle.
Hub and Drum
Removal, Service and Installation
See " Hub and Drum " Eaton Single-Speed A xle.
PISTON AIR-SHIFT SYSTEM
An a ir shift control is used in conjunction with the
Eaton M odel 19201 tw o-speed axle. S erv ice operations
and trouble shooting procedu res pertaining to this s y s ­
tem a re as outlined below.
Trouble Shooting (Refer to Figure 8 1 )
If axle w ill not shift, test system and components as
follow s.
NOTE: T est lamp voltage must be same as
system rated voltage.
Circuit Breaker Check
Disconnect circ u it b rea k er lead w ire at term inal A and
connect test lamp fro m
switch and ob serve test lamp.
a. If lamp lights and stays on, c irc u it b rea k er and
lead w ire are satisfa ctory.
b. If lamp does not light, check fo r poor e le c tric a l
connections o r broken lead w ire .
and connections are sa tisfactory, circu it brea k er
is faulty.
c. If lamp does not light im m ediately but then starts
to flash (also a
b reak er may be heard), the c irc u it break er is
faulty.
Control Switch and W iring Harness Check
If trouble in control switch o r w irin g harness is sus­
pected, visu ally check harness fo r damaged o r worn
insulation that could cause a ground connection. Check
fo r accidental grounding o f w ire
m ission le v e r . Check fo r short circu its between w ire
term in als. Check fo r poor insulation o r accidental ground
at end o f lead w ire D.
To determ ine condition of control switch, a new con­
t r o l switch may be tem p ora rily installed. H ow ever, if
d esired , control switch operation may be checked with a
test lamp, using the follow ing procedu re.
Disconnect lead w ire s at B and C. Turn ignition switch
on and altern ately connect test lamp leads to disconnected
lead w ire s . Operate control switch and ob serve test lamp
fo r the follow ing conditions.
When test lamp is connected to lead B, lamp should
light in low range position of control switch.
should go out with control switch in high range position.
When test lamp is connected to lead C, lamp should
light in high range position o f control switch.
should go out with control switch in low range position.
If test lamp indications are c o r r e c t in the above tests,
current supply to speedom eter adapter and solenoid valve
is co rre c t.
If test lamp does not light, trouble may be a short
circu it in w irin g harness o r control switch, o r a w ire
and Installation" Eaton
A to ground. Turn on ignition
If lead w ire
faint clickin g of the circu it
term in als to tran s­
Lamp
Lamp
CHEVROLET TRUCK SERVICE MANUAL