1993 DODGE TRUCK check oil

3
- 42
REAR
SUSPENSION
AND
AXLE

SPECIAL TOOL
D-111
PRESS

DRIVE

PINION GEAR
SHAFT
REAR BEARING"
INSTALLATION

TOOL
SPECIAL
TOOL
C-4171 J9203-65 DRIVE
PINION GEAR
OIL

SLINGER

J9302-68

Fig.
33
Pinion
Rear Bearing Cup
installation
Fig.
35
Pinion
Rear Bearing
Installation

BEARING
CUP

INSTALLATION
TOOL
C-4203
DRIVER

HANDLE
TOOL

C-4171
SPECIAL

TOOL
C-3718
DIFFERENTIAL

HOUSING

SPECIAL
TOOL

C-3281

Fig.
34
Pinion
Front Bearing Cup
Installation
(13) Tighten the yoke nut to 339-366 N-m (250-270
ft. lbs.) torque. (14) Check bearing preload torque with an inch
pound torque wrench (Fig. 37). The torque necessary
to rotate the pinion gear should be;
• Original Bearings — 1-3 Nnn (10-20 in. lbs.)
• New Bearings — 2-5 Nnn (20-40 in. lbs.)
If the preload torque is not within the specified tol­
erance, correct the shim thickness accordingly (Fig.

38);

• Increase the preload torque, decrease the shim
thickness
• Decrease the preload torque, increase the shim
thickness
J9103-21

Fig.
36
Pinion
Yoke
Installation

(15) Remove the pinion yoke nut and washer. Use
Remover C-452 and Wrench C-3281 to remove the
pinion yoke (Fig. 39).
(16) Apply a light coating of gear lubricant on the
lip of pinion seal. Install the new seal (Fig. 40);
© Model 60 use Installer C-3719-A and Handle C-4735
• Model 70 use Installer C-359 and Handle C-4735 (17) Install the yoke with Installer C-3718 and
Wrench C-3281 (Fig. 36).

•

REAR
SUSPENSION
AND
AXLE
3 - 4S

SPACER

DEPTH SHIMS
HERE
REAR
PINION

BEARING

SHAFT

BEARING
CAP ARBOR
J9203-53
Fig.
45 Depth
Shim(s)
Selection

HAMMER
DRIVER HANDLE
J9203-58

Fig.
46 Rear Bearing Cup
Removal

(11) Position depth shims in housing rear bearing
cup bore.
(12) Install the pinion rear bearing cup (Fig. 42);
• Model 60 use Installer D-lll and Handle C-4171
• Model 70 use Installer C-4204 and Handle C-4171 Ensure the cup is correctly seated.
(13) If the depth of mesh has been followed accord­
ing to the instructions above, good gear teeth contact
should exist.
(14) Install the rear bearing (and slinger if used)
on the pinion gear with Installer C-3095-A until
completely seated (Fig. 47).
(15) Install pinion in housing bore.
(16) Assemble preload shims onto pinion and in­
stall the pinion gear in housing.
PRESS

DRIVE

PINION GEAR
SHAFT

REAR
BEARING
^
INSTALLATION
TOOL

DRIVE

PINION GEAR OIL

SUNGER

J9302-68

Fig.
47
Pinion
Rear Bearing
Installation
(17) Install pinion front bearing, oil slinger, yoke,
washer and nut. Install the yoke with Installer
C-3718 and Wrench C-3281 (Fig. 48).

SPECIAL
TOOL

C-3718
DIFFERENTIAL
HOUSING

SPECIAL
TOOL

C-3281

J9103-21

Fig.
48
Pinion
Yoke
Installation

(18) Tighten the yoke nut to 339-366 Nnn (250-270
ft. lbs.) torque.
(19) Check bearing preload torque with an inch
pound torque wrench (Fig. 49). The torque necessary to rotate the pinion gear should be;
• Original Bearings — 1-3 Nnn (10-20 in. lbs.)
• New Bearings — 2-5 Nnn (20-40 in. lbs.)

5 - 2 BRAKES
• CAUTION:
Never
use gasoline,
kerosene,
alcohol,

motor
oil, transmission
fluid,
or any
fluid
containing

mineral
oil to
clean
the system
components.
These

fluids
damage
rubber
cups and seals. If system

contamination
is suspected,
check
the
fluid
for
dirt,

discoloration,
or
separation
into
distinct
layers.
Drain
and
flush
the system
with
new
brake
fluid
if

contamination
is suspected.

BRAKE
SAFETY PRECAUTIONS WARNING: DUST AND DIRT ON BRAKE PARTS

THAT
ACCUMULATES DURING NORMAL USE MAY CONTAIN ASBESTOS FIBERS. BREATHING
EXCES­

SIVE
CONCENTRATIONS OF ASBESTOS FIBERS

CAN
CAUSE SERIOUS BODILY HARM. EXERCISE

CARE
WHEN SERVICING BRAKE COMPONENTS.
DO NOT CLEAN BRAKE COMPONENTS
WITH
COM­

PRESSED
AIR OR BY DRY BRUSHING. USE A VAC­ UUM CLEANER SPECIFICALLY DESIGNED FOR
REMOVING BRAKE DUST
THAT
MAY ASBESTOS

FIBERS.
IF A SUITABLE VACUUM CLEANER IS NOT

AVAILABLE,
CLEANING SHOULD BE DONE USING

A
WATER DAMPENED CLOTH. DO NOT CREATE DUST BY SANDING, GRINDING, OR SHAVING

BRAKE
LININGS UNLESS PROPERLY VENTED
EQUIPMENT IS USED. DISPOSE OF ALL DUST AND
DIRT
THAT
MAY CONTAIN ASBESTOS FIBERS IN

SEALED
BAGS OR CONTAINERS. THIS WILL MINI­ MIZE EXPOSURE TO YOURSELF AND OTHERS.
FOLLOW ALL RECOMMENDED PRACTICES PRE­

SCRIBED
BY THE OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION AND THE ENVIRON­
MENTAL PROTECTION AGENCY FOR THE HAN­
DLING, PROCESSING, AND DISPOSITION OF DUST
OR DIRT WHICH MAY CONTAIN ASBESTOS FI­
BERS.

•

BRAKES
i - 3 BRAKE DIAGNOSIS

INDEX

page

Brake
Warning Lights
3

Diagnosing
Brake Problems .................
4

Diagnosis
Procedures
3

Low
Vacuum
Switch—Diesel
Models
3
page

Master
Cylinder/Power Booster Test
5

Power
Booster
Check
Valve Test .............
6

Power
Booster
Vacuum
Test .................
6

Testing Diesel
Engine
Vacuum
Pump
Output
.... 6

DIAGNOSIS
PROCEDURES
Brake diagnosis involves determining
if the
prob­
lem
is
related
to a
mechanical, hydraulic
or
vacuum
operated component.
A
preliminary check, road test­
ing
and
component inspection
can all be
used
to de­

termine
a
problem cause. Road testing will either verify proper brake opera­
tion
or
confirm
the
existence
of a
problem. Compo­ nent inspection will,
in
most cases, identify
the
actual part causing
a
problem. The first diagnosis step
is the
preliminary check. This
involves inspecting fluid level, parking brake action,
wheel
and
tire condition, checking
for
obvious leaks
or

component damage
and
testing brake pedal response. A road test will confirm
the
existence
of a
problem.
Final diagnosis procedure involves road test analysis and
a
visual inspection
of
brake components.

BRAKE
WARNING LIGHTS
The
red
brake warning light
is
connected
to the

parking brake switch
and to the
pressure differential switch
in the
combination valve. The
red
light will illuminate when
the
parking
brakes
are
applied
or
when
a
fluid pressure drop
oc­
curs
in the
front
or
rear brake circuit.
The
light will
also illuminate
for
approximately
2-4
seconds
at en­

gine start
up.
This
is a
self test feature designed
to

check bulb
and
circuit operation each time
the en­

gine
is
started. The amber antilock light
is
connected
to the
anti-
lock rear brake hydraulic valve.
The
light will illu­
minate
if a
fault occurs within
the
antilock system.

LOW VACUUM SWITCH-DIESEL MODELS
On diesel models,
the red
brake warning light
is
also
used
to
alert
the
driver
of a low
brake booster vacuum
condition.
The
warning light
is in
circuit with
a
vacuum
warning switch mounted
on the
driver side fender
panel.
The
vacuum side
of the
switch
is
connected
to the

power brake booster.
The
electrical side
of the
switch
is
connected
to the
brake warning light. The
low
vacuum switch monitors booster vacuum
level whenever
the
engine
is
running.
If
booster vac­
uum falls below
8.5
inches vacuum
for a
minimum
of
10 seconds,
the
switch completes
the
circuit
to the

warning light causing
it to
illuminate.
The
warning light
is
designed
to
differentiate between
a low
vac­
uum condition
and a
hydraulic circuit fault.

PRELIMINARY
BRAKE CHECK
(1) Check condition
of
tires
and
wheels. Damaged
wheels
and
worn, damaged,
or
underinflated tires
can
cause pull, shudder, tramp,
and a
condition similar
to
grab.

(2)
If
complaint
was
based
on
noise when braking,
check suspension components. Jounce front
and
rear
of

vehicle
and
listen
for
noise that might
be
caused
by

loose, worn
or
damaged suspension
or
steering compo­

nents.

(3) Inspect brake fluid level
and
condition. Note
that
the
front disc brake reservoir fluid level will drop
in
proportion
to
normal lining wear. Also note
that brake fluid tends
to
darken over time. This
is normal
and
should
not be
mistaken
for
con­
tamination.
If the
fluid
is
still clear
and
free
of

foreign material,
it is OK.

(a)
If
fluid level
is
abnormally
low,
look
for
evi­
dence
of
leaks
at
calipers, wheel cylinders, brake-
lines
and
master cylinder.
(b)
If
fluid appears contaminated, drain
out a

sample.
If
fluid
is
separated into layers,
or
obvi­
ously contains
oil or a
substance other than brake
fluid,
the
system seals
and
cups will have
to be re­

placed
and the
hydraulic system flushed.
(4) Check parking brake operation. Verify free
movement
and
full release
of
cables
and
pedal. Also
note
if
vehicle
was
being operated with parking
brake partially applied.
(5) Check brake pedal operation. Verify that pedal
does
not
bind
and has
adequate free play.
If
pedal
lacks free play, check pedal
and
power booster
for be­

ing loose
or for
bind condition.
Do not
road test until
condition
is
corrected.
(6)
If
components checked appear
OK,
road test
the

vehicle.

ROAD
TESTING (1)
If
complaint involved
low
brake pedal, pump
the pedal
and
note
if the
pedal comes back
up to
nor­ mal height.
(2) Check brake pedal response with transmission
in Neutral
and
engine running. Pedal should remain
firm under steady foot pressure.

•

BRAKES
5 - 5 Disc brake rotors with excessive lateral runout or
thickness variation, or out of round brake drums are
the primary causes of pulsation. Other causes are loose
wheel bearings or calipers and worn, damaged tires.

PULL A
front pull condition could be the result of con­
taminated lining in one caliper, seized caliper piston,
binding caliper, loose caliper, loose or corroded slide

pins,
improper brakeshoes, or a damaged rotor.
A worn, damaged wheel bearing or suspension compo­
nent are further causes of pull. A damaged front tire (bruised, ply separation) can also cause pull.
A common and frequently misdiagnosed pull condi­
tion is where direction of pull changes after a few
stops.
The cause is a combination of brake drag fol­
lowed by fade at one of the brake units.
As the dragging brake overheats, efficiency is so
reduced that fade occurs. Since the opposite brake
unit is still functioning normally, its braking effect is
magnified. This causes pull to switch direction in fa­
vor of the normally functioning brake unit.
When diagnosing a change in pull condition, re­
member that pull will return to the original direction
if the dragging brake unit is allowed to cool down (and is not seriously damaged).

REAR BRAKE GRAB
OR
PULL
Rear grab or pull is usually caused by an improperly
adjusted or seized parking brake cable, contaminated
lining, bent or binding shoes and support plates, or im­
properly assembled components. This is particularly
true when only one rear wheel is involved. However,
when both rear wheels are affected, the master cylinder or proportioning valve could be at fault.

BRAKES
DO NOT
HOLD
AFTER
DRIVING
THROUGH
DEEP
WATER
PUDDLES

This condition is generally caused by water soaked
lining. If the lining is only wet, it can be dried by driv­
ing with the brakes very lightly applied for a few min­

utes.
However, if the lining is thoroughly wet and dirty,
disassembly and cleaning will be necessary.

BRAKE NOISE

Squeak/Squeal
Brake squeak or squeal may be due to linings that
are wet or contaminated with brake fluid, grease, or oil. Glazed linings and rotors with hard spots can also con­
tribute to squeak. Dirt and foreign material embedded in the brake lining can also cause squeak/squeal.
A very loud squeak or squeal is frequently a sign of
severely worn brake lining. If the lining has worn
through to the brakeshoes in spots, metal-to-metal con­
tact occurs. If the condition is allowed to continue, ro­ tors can become so scored that replacement is necessary.
Thump/Clunk

Thumping or clunk noises during braking are fre­
quently not caused by brake components. In many

cases,
such noises are caused by loose or damaged steering, suspension, or engine components. How­
ever, calipers that bind on the slide pins, or slide sur­

faces,
can generate a thump or clunk noise. Worn
out, improperly adjusted, or improperly assembled
rear brakeshoes can also produce a thump noise.

Chatter
Brake chatter is usually caused by loose or worn
components, or glazed/burnt lining. Rotors with hard
spots can also contribute to chatter. Additional
causes of chatter are out of tolerance rotors, brake
lining not securely attached to the shoes, loose wheel
bearings and contaminated brake lining.
Brakelining Contamination Brakelining contamination is usually a product of
leaking calipers or wheel cylinders, driving through
deep water puddles, or lining that has become cov­
ered with grease and grit during repair.
Wheel and
Tire
Problems Some conditions attributed to brake components
may actually be caused by a wheel or tire problem.
A damaged wheel can cause shudder, vibration and
pull. A worn or damaged tire can also cause pull.
Severely worn tires with very little tread left can
produce a grab-like condition as the tire loses and re­ covers traction. Flat-spotted tires can cause vibration and wheel
tramp and generate shudder during brake operation. A tire with internal damage such as a severe
bruise or ply separation can cause pull and vibration.

MASTER
CYLINDER/POWER BOOSTER TEST
(1) Start engine and check booster vacuum hose
connections. Hissing noise indicates a vacuum leak. Correct any leaks before proceeding. (2) Stop engine and shift transmission into Neu­
tral (3) Pump brake pedal until all vacuum reserve in
booster is depleted. (4) Press and hold brake pedal under light foot
pressure. (a) If pedal holds firm, proceed to step (5).
(b) If pedal does not hold firm and falls away,
master cylinder is faulty (internal leakage). (5) Start engine and note pedal action. (a) If pedal falls away slightly under light foot
pressure then holds firm, proceed to step (6). (b) If pedal is effort is high, or no pedal action is
discernible, power booster or vacuum check valve is
faulty. Install known good check valve and repeat steps (2) through (5).

•

BRAKES
i - 7
BRAKE
ADJUSTMENTS-BRAKE
BLEEDING

INDEX

page

Brake
Fluid and Level 7

Brake
System
Bleeding 8
Rear
Brake
Adjustment 7

BRAKE
FLUID
AND
LEWEL

RECOMMENDED
FLUID The only brake fluid recommended for AD models
is Mopar brake fluid, or an equivalent fluid meeting SAE
J1703
and DOT 3 standards.
Use new brake fluid only, to top off the master
cylinder or refill the system* Never use re­
claimed fluid, fluid not meeting the
SAE/DOT
standards, fluid marked 70R1, or fluid from a
container that has been left open for any length
of time. Using non recommended or unspecified
fluid can result in brake failure after hard pro­ longed braking.

BRAKE
FLUID
LEWEL Always clean the master cylinder cover before
checking fluid level. If not cleaned, dirt from the
cover could enter the fluid. Also check the cover seal
and replace it if torn or distorted.
Correct fluid level is to the bottom of the ring in­
dicators on models with a plastic reservoir and to
within 1/4 inch of the reservoir rim on all others. If necessary, add fluid to bring up to the proper level.
Note that on disc brake equipped vehicles, fluid level can be expected to fall as the brake pads wear.

BRAKE
FLUID
CONTAMINATION
Oil in the fluid will cause brake system rubber
seals to soften and swell. The seals may also become
porous and begin to deteriorate.
If fluid contamination is suspected, drain off a sam­
ple from the master cylinder. A suction gun or simi­ lar device can be used for this purpose.
Empty the drained fluid into a glass container.
Contaminants in the fluid will cause the fluid to sep­
arate into distinct layers. If contamination has oc­
curred, the system rubber seals, hoses and cups must
be replaced and the system thoroughly flushed with clean brake fluid.
Remember that brake fluid tends to darken
over time. Do not confuse this normal condition
with contamination.

REAR
BRAKE
ADJUSTMENT
The rear drum brakes are equipped with a self ad­
justing mechanism. Under normal circumstances, the only time adjustment is required is when the brake-
page

Stop
Light Switch Adjustment 9

Wheel
Nut Tightening 9
shoes are replaced; removed for access to other parts; or when one or both drums are replaced.
Adjustment can be performed with a standard
brake gauge or with adjusting tool C-3784.

ADJUSTMENT
WITH
STANDARD
BRAKE
GAUGE
(1) Verify that left/right automatic adjuster lever
and cable are properly connected and that parking
brakes are fully released. Be sure there is slack in cables.
(2) Insert brake gauge in drum. Expand gauge un­
til gauge inner legs contact drum braking surface. Then lock gauge in position (Fig. 1).

Fig.
1 Adjusting Gauge To Brake
Drum

(3) Reverse gauge and install it on brakeshoes
(Fig. 2). Position gauge legs at shoe centers as
shown. If gauge does not fit (too loose/too tight), ad­
just shoes. (4) Pull the shoe adjuster star wheel away from
the automatic adjuster lever.
(5) Turn the adjuster star wheel (by hand) to ex­
pand or retract the brakeshoes. Continue adjustment until the gauge outside legs are a light drag-fit on
the shoes (Fig. 2).
(6) Repeat adjustment at the opposite brakeshoe
assembly. (7) Install the brake drums and wheels and lower
the vehicle.
(8) Make final adjustment. Drive vehicle and make
one forward stop followed by one reverse stop. Repeat
procedure 8-10 times to actuate adjuster mechanism and equalize adjustment. Bring vehicle to complete

•

BRAKES
5 - 13
COMBINATION VALVE OPERATION

METERING (HOLD-OFF) VALVE The metering valve is used to balance brake action
between the front disc and rear drum brakes. The
valve meters (holds-off) full apply pressure to the front disc brakes until the rear brakeshoes are in full
contact with the drums.
The valve is designed to maintain front brake fluid
pressure at 3-30 psi until the hold-off limit of 117 psi is reached. At this point, the metering valve opens completely permitting full fluid apply pressure to the
front disc brakes.
PRESSURE DIFFERENTIAL SWITCH AND VALVE The pressure differential switch is connected to the
brake warning light. The switch is triggered by movement of the switch valve. The purpose of the switch is to monitor fluid pressure in the separate
front/rear brake hydraulic circuits.
A decrease or loss of fluid pressure in either hy­
draulic circuit will cause the switch valve to shuttle
forward or rearward in response to a pressure differ­ ential.
Movement of the switch valve will push the switch
plunger upward. This closes the switch internal con­ tacts completing the electrical circuit to the warning light. The switch valve will remain in an actuated
position until repair restores system pressures to nor­ mal levels.

COMBINATION VALVE TESTING
TESTING METERING VALVE Metering valve operation can be checked visually
and with the aid of a helper.
Observe the metering valve stem while a helper
applies and releases the brakes. If the valve is oper­
ating correctly, the stem will extend slightly when
the brakes are applied and retract when the brakes are released.
If the valve is faulty, replace the entire combina­
tion valve as an assembly.
TESTING PRESSURE DIFFERENTIAL SWITCH (1) Have helper sit in drivers seat to observe brake
warning light and to operate brake pedal.
(2) Raise vehicle on hoist.
(3) Connect bleed hose to left or right rear wheel
cylinder. Then immerse hose end in glass jar par­
tially filled with brake fluid.
(4) Have helper press and hold brake pedal all the
way down and observe warning light.
(a) If warning light illuminates, switch is operat­
ing correctly. (b) If light fails to illuminate, check circuit fuse,
bulb and wiring. Repair as necessary and repeat test steps (3) and (4). (5) If warning light still fails to illuminate, check
brakelight and park brake switches (and wiring) with test lamp. Repair or replace parts as necessary and test differential pressure switch operation again.
(6) If warning light still does not illuminate,
switch is faulty. Replace combination valve, bleed
brakes and verify proper switch and valve operation.

COMBINATION VALVE REMOVAL/INSTALLATION
VALVE REMOVAL (1) Raise vehicle on hoist.
(2) Mark or tag brake lines connected to valve for
assembly reference.
(3) Disconnect lines at valve (Fig. 8).
(4) Disconnect wires from differential pressure
switch.
(5) Remove bolts attaching valve to frame bracket
and remove valve.
VALVE INSTALLATION (1) Mount new valve on bracket and tighten valve
and bracket screws/nuts securely.
(2) Connect brakelines to valve. Tighten fittings to
16 N*m (145 in. lbs.)
(3) Connect wires to pressure differential switch
terminal. (4) Bleed brakes.
(5) Lower vehicle and verify proper brake opera­
tion.

BRAKE
LINES AND
HOSES

BRAKE LINE AND HOSE INSPECTION Flexible rubber hose is used at both front brakes
and at the rear axle junction block. Inspect the hoses
whenever the brake system is serviced, at every en­ gine oil change, or whenever the vehicle is in for ser­

vice.

Inspect the hoses for surface cracking, scuffing, or
worn spots. Replace any brake hose immediately if
the fabric casing of the hose is exposed by cracks or abrasion.
Also check brake hose installation. Faulty installa­
tion can result in kinked, twisted hoses, or contact with the wheels and tires or other chassis compo­
nents.
All of these conditions can lead to scuffing,
cracking and eventual failure.
The steel brake lines should be inspected periodi­
cally for evidence of corrosion, twists, kinks, leaks, or
other damage. Heavily corroded lines will eventually
rust through causing leaks. In any case, corroded or damaged brake lines should be replaced.

•

BRAKES
5 - 23
VACUUM PUMP OPERATION

Vacuum pump output is transmitted to the power
brake booster through a supply hose. The hose is con­ nected to an outlet port on the pump housing and to
the check valve in the power brake booster.
Pump output ranges from a minimum of 8.5 to 25
inches vacuum. The pump rotor and vanes are rotated by the pump
drive gear. The drive gear is operated by the cam­
shaft gear. Booster vacuum level is monitored by a warning
switch (Fig. 2). The switch consists of a vacuum
chamber that measures vacuum level and a sensor in
circuit with the brake warning light. The vacuum chamber is connected to the booster
check valve by a vacuum supply hose. A wire har­
ness connects the switch sensor to the brake warning
light. If booster vacuum falls below 8.5 inches for 8-10 seconds or more, the switch sensor completes
the circuit to the warning light causing it to illumi­

nate.

VACUUM PUMP DIAGNOSIS
Vacuum pump diagnosis involves checking pump
output with a vacuum gauge. The low vacuum warn­
ing switch can also be checked with a vacuum gauge.
Refer to the diagnosis procedure in this section. A standard vacuum gauge can be used to check
pump output when necessary. Simply disconnect the
pump supply hose and connect a vacuum gauge to
the outlet port for testing purposes. Vacuum should
hold steady in a range of approximately 8.5 to 25 inches at various engine speeds.
DIAGNOSING LOW VACUUM OUTPUT CONDITION A low booster vacuum condition or a faulty low
vacuum warning switch will cause the brake warn­ ing light to illuminate. If the light does go on and in­
dicates the existence of a low vacuum condition,
check the vacuum pump, booster and warning switch
as follows:
(1) Check vacuum pump oil feed line. Verify that
line connections are secure and not leaking. If leak­ age is noted and pump is noisy, replace pump.
(2) Disconnect supply hose to booster. Connect vac­
uum gauge to this hose and run engine at various
throttle openings. Output should range from 8.5 to 25 inches vacuum. If vacuum is consistently below
8.5 inches, problem is with vacuum hoses or pump
component. If output is within specified limits, con­
tinue testing.
(3) Check booster operation as described in diagno­
sis section. Replace check valve, vacuum hoses, or
booster if necessary. However, if booster operation is correct but warning light is still on, continue testing. (4) Disconnect vacuum hose at warning switch.
Plug hose and connect hand vacuum pump to switch. (5) Start and run engine.
(6) Apply 8.5 to 9 inches of vacuum to warning
switch and observe warning light. If light goes out,
switch vacuum hose is either loose or leaking. If
light remains on, leave engine running and continue
testing.
(7) Apply 20-25 inches vacuum to switch and ob­
serve warning light operation. If light now goes out,
switch is at fault and should be replaced. If light re­
mains on, continue testing.
(8) Reconnect vacuum hoses and replace original
warning switch with known good switch. Run engine and observe warning light operation. If light is now
off, old switch is faulty. If light remains on, problem
is in wiring between switch and warning light.

VACUUM-STEERING PUMP
ASSEMBLY
REMOVAL
(1) Disconnect battery negative cable.
(2) Position drain pan under power steering pump.
(3) Disconnect vacuum and steering pump hoses
from respective pumps (Fig. 3).

Fig.
3
Vacuum
And Steering
Pump Hose
Connections

(4) Disconnect oil pressure sender wires at sender
(Fig. 4).
(5) Remove oil pressure sender (Fig. 4).
(6) Disconnect lubricating oil feed line from fitting
at underside of vacuum pump (Fig. 5).
(7) Remove lower bolt that attaches pump assem­
bly to engine block (Fig. 6).
(8) Remove bottom, inboard nut that attaches
adapter to steering pump (Fig. 6). This nut secures a
small bracket to engine block. Nut and bracket must
be removed before pump assembly can be removed from block.