gas type DODGE TRUCK 1993 Service Repair Manual

0 - 2
LUBRICATION
AND
MAINTENANCE

• Commercial service
When a vehicle is continuously subjected to severe
driving conditions, lubricate:
• Body components
• All the driveline coupling joints
• Steering linkage More often than normal driving conditions

DUSTY
AREAS
With this type of severe driving condition, special
care should be given to the:
• Engine air cleaner filter
• PCV filter
• Crankcase ventilation system
• Brake booster control valve air filter. Verify that the filters and the associated compo­
nents are clean. Also verify that they are functioning
effectively. This will minimize the amount of abra­ sive particles that enter the engine.

OFF-ROAD
(4WD)
OPERATION
After off-road (4WD) operation, inspect the under­
side of the vehicle. Inspect the:
• Tires
• Body structure
• Steering components
• Suspension components • Exhaust system
• Threaded fasteners

HARSH
SURFACE ENVIRONMENTS
After extended operation in harsh environments,
the brake drums, brake linings, and rear wheel bear­ ings should be inspected and cleaned. This will pre­
vent wear and erratic brake action.

ROUTINE MAINTENANCE
The following routine maintenance is recommended
on a monthly basis: TIRES—Inspect the tires for unusual wear/damage.
Determine if the inflation pressure is adequate for
the vehicle load. BATTERY—Inspect and clean the terminals.
Tighten the terminals if necessary. FLUIDS—Determine if the component fluid levels
are acceptable. Add fluid, if necessary. LIGHTS/ELECTRICAL—Test all the electrical sys­
tems in the vehicle for proper operation. It is also recommended that the engine oil and the
washer fluid level be determined at each fuel fill-up.

VEHICLE
NOISE CONTROL
Vehicles with a GVWR of 4 535 kg (10,000 lbs), or
more, are required to comply with Federal Exterior Noise Regulations (Fig. 2).
VEHICLE
NOISE
EMISSION
CONTROL INFORMATION

DATE
OF
VEHICLE
MANUFACTURE

THIS
VEHICLE CONFORMS
TO
U.S. EPA REGULATIONS FOR NOISE EMISSION

APPLICABLE
TO
MEDIUM
AND HEAVY
DUTY
TRUCKS. THE
FOLLOWING
ACTS OR THE CAUSING THEREOF BY ANY PERSON ARE PROHIBITED BY THE NOISE CONTROL ACT
OF 1972. (A) THE
REMOVAL
OR

RENDERING
INOPERATIVE, OTHER
THAN
FOR
PURPOSES
OF
MAINTENANCE,
REPAIR.
OR REPLACEMENT, OF ANY NOISE CONTROL DEVICE OR ELEMENT OF
DESIGN
(LISTED
IN
THE
OWNERS
MANUAL)
INCORPORATED
INTO
THIS
VEHICLE
IN COMPLIANCE
WITH
THE NOISE CONTROL
ACT:
(B) THE
USE
OF
THIS
VEHICLE
AFTER SUCH DEVICE
OR
ELEMENT
OF
DESIGN HAS BEEN REMOVED
OR
RENDERED
INOPERATIVE.

PU626D

Fig.
2 Vehicle
Noise
Emission
Control Information
Label

UNAUTHORIZED
DEFEAT
OF
NOISE
CONTROL COMPONENTS
Federal law prohibits removal, altering or other­
wise defeating any noise control component. This in­
cludes before or after the vehicle is in use. Federal
law also prohibits the use of a vehicle after a noise
control component is defeated.

REQUIRED MAINTENANCE/SERVICE
FOR
NOISE
CONTROL

The following maintenance is required after each
6-month or 9 600 km (6,000 miles) interval. This will
ensure that the vehicle noise control components are
operating properly.

EXHAUST SYSTEM
Inspect exhaust system for exhaust leaks and dam­
aged components. The exhaust hangers, clamps and
U-bolts should be attached and in good condition.
Burned or ruptured mufflers, damaged exhaust pipes should be replaced. Refer to Group 11—Exhaust Sys­
tem/Intake Manifold for service information.

AIR
FILTER
HOUSING/CANISTER
Inspect the air filter assembly for proper fit. Verify
the cover is securely attached to the housing/canis­
ter. Inspect all the air filter housing hoses for con­ nections. The gasket between the air filter housing and throttle body must be in good condition. The air
filter element should be clean and serviced according
to the maintenance schedule.

FUEL
REQUIREMENTS
GASOLINE
ENGINES
All engines require the use of unleaded gasoline to
reduce the effects of lead to the environment. Also unleaded fuel is necessary to prevent damage to the
catalytic converter/02 sensor. The fuel must have a
minimum octane rating of 87 based on the (R + M)/2
calculation method.

•

LUBRICATION AND MAINTENANCE
0 - 3
CAUTION: UNLEADED FUEL ONLY must
be
used
in

vehicles equipped
with
a
catalyst emission
control

system.
All
vehicles have reminders
printed
on the
instrument
panel below
the
fuel
gauge
and on the

fuel
filler
door.
The
vehicles also have
fuel
filler

tubes
that
are
specially designed
to
accept only
the
small-diameter nozzles.
It is
illegal
to
bypass
the

design
of an
unleaded
fuel
filler
tube.

DIESEL ENGINES All
Ram
Truck
and Ram
Cab/Chassis Diesel
en­

gines normally
can use
number
2D
Diesel fuel
for

most year-round operations.
A
fuel conforming
to

ASTM Specification D-975
is
recommended.
For ex­

treme cold-weather, number
ID
Diesel fuel
is
recom­ mended.

CLASSIFICATION
OF
LUBRICANTS
Lubricating fluids
and
chassis lubricants
are
clas­
sified according
to
standards recommended
by the:
• Society
of
Automotive Engineers
(SAE)

• American Petroleum Institute
(API)

• National Lubricating Grease Institute (NLGI)
ENGINE
OIL

SAE
VISCOSITY
GRADE
An
SAE
viscosity grade
is
used
to
specify
the
vis­
cosity
of
engine
oil. SAE 30
specifies
a
single viscos­
ity engine
oil.

Engine oils also have multiple viscosities. These
are specified with
a
dual
SAE
viscosity grade which
indicates
the
cold-to-hot temperature viscosity range (Fig.
3).

API
SERVICE
GRADE
The
API
Service Grade specifies
the
type
of
perfor­
mance
the
engine
oil is
intended
to
provide.
The API
Service Grade specifications also apply
to
energy con­
serving engine oils
(Fig. 3).

For maximum gasoline engine protection,
use API

Service Grade
SG,
SG/CD
or
SG/CE engine
oil.

For maximum Diesel engine protection,
use

API Service
CE or
SG/CE engine
oil.

GEAR LUBRICANTS A dual grade
is
also used
to
specify
the
viscosity
of

multi-purpose gear lubricants.
The
API
grade designation identifies gear lubri­
cants
in
terms
of
recommended usage.
OIL

QUALITY

SAE

VISCOSITY
GRADE

FUEL

ECONOMY

NOTATION
J91004

Fig.
3 SAE Oil
Viscosity Grade
& API
Service
Grade
CHASSIS COMPONENT
AND
WHEEL BEARING
LUBRICANTS The chassis
and
wheel bearing lubricants
are
iden­
tified
by the
NLGI Certification Symbol.
The
symbol
contains
a
coded designation. This identifies
the us­
age
and
quality
of the
lubricant.
The letter
G
within
the
symbol designates wheel
bearing lubricant.
The
letter
L
designates chassis
lu­

bricant. When
the
letters
are
combined,
the
lubricant can
be
used
for
dual applications.
Use
only lubricants
that display
the
NLGI Certification Symbol.

NATIONAL LUBRICATING
GREASE
INSTITUTE
NLGI

AUTOMOTIVE
WHEEL BEARING
&
CHASSIS LUBRICANT
GC-LB

-CERTIFICATION

SYMBOL
—
USAGE
AND

QUALITY
DESIGNATION
J920W7

Fig.
4
NLGI
Lubricant Container
Certification/
Identification
Symbol
LUBRICATION
AND
REPLACEMENT
PARTS

RECOMMENDATION
Ram Trucks
are
engineered
to
provide many years
of dependable operation. However, lubrication service
and maintenance
are
required
for
each vehicle. When
necessary, MOPAR®brand lubricants
and
genuine
re­

placement parts
are
recommended.

0 - 6
LUBRICATION
AND
MAINTENANCE
GASOLINE ENGINE MAINTENANCE SCHEDULE

HEAVY
DUTY
CYCLE

Inspection and service is also necessary anytime
a
malfunction is observed or suspected.
When both
time
and mileage
are
Miles (Thousand)

shewn,
follow
the
interval

which occurs first. Kilometers (Thousand) 6
12 18 24
30 36 42 48 54
60 66 72

78
82V2
84 90
96
102 108
When both
time
and mileage
are
Miles (Thousand)

shewn,
follow
the
interval

which occurs first. Kilometers (Thousand) 9.6 19 29
38 48 58 67 77
85 96 106 116
125 132
135
145
154 164
174

Coolant
Condition, Coolant
Hoses/Clamps
X
X X X
X X X X
X X X X
X X X
X X X

Exhaust
System
—
Check
X X X X X X X X X X X
X X X X X
X X

Oil
—
Change
(6
Months)
X X X X X X X
X X

X
X
X

X X X

X X
X

Oil
Filter
—
Change (2nd
Oil
Change)
X X X X
X X
X X
X

Drive Belt Tension
—
Inspect
&
Adjust
X' X
X1

X X' X

Drive Belts (V-Type)
—
Replace
X

Air
Filter/Air
Pump
Air
Filter
—
Replace
X X X
X

Crankcase
Inlet
Air
Filter
(6 &
8
Cyl.
Eng.
Only)
—
Clean
X X
X X

Spark
Plug
—
Replace
X X X

Fuel
Filter
—
Replace as necessary

Coolant
—
Flush/Replace
(36
months)
& 24
months/48
000 km

(30,000
miles)
thereafter
X
EGR
Valve
&
Tube
—
Replace X2

EGR
Tube
—
Clean Passengers
X2
PCV
Valve
—
Replace X2

Vacuum
Emission
Components
—
Replace
X

Ignition Timing
—
Adjust
to
Specs,
as necessary X
Ignition Cables, Distributor Cap
&
Rotor
—
Replace
X

Manifold Heat Control Valve
—
Lubricate
X

Battery
—
Replace X

Oxygen
Sensor
—
Replace
X2

1 For California vehicles, this maintenance is recommended
by
Chrysler Motors
to the
owner but, is not
required
to
maintain the
warranty
on the
air
pump drive
belt.

2 Requires
Emission
Maintenance Reminder Light.
If
so equipped, these parts
are to be
replaced
at the
indicated mileage,
or
when the
emissions
maintenance reminded light remains on continuously
with
the key in the
"on" position, whichever occurs first.
J9100-20

DIESEL
ENGINE
MAINTENANCE
SCHEDULE
HEAVY
DUTY
CYCLE
Inspection
and
service
is
also
necessary
any
time
a
malfunction
is
observed
or
suspected.

Iff both
time
and distance Miles (Thousand)
are listed, use the
interval

that
ends
first. Kilometers (Thousand) 6
12
18 24
30 36 42

4S
54
60 66
72 78
84 90 96
102 108
Iff both
time
and distance Miles (Thousand)
are listed, use the
interval

that
ends
first. Kilometers (Thousand) 9,6 19
29
38 48 58 67

77

85 96 106
116 125 135 145 154
164 174

Coolant
Condition, Coolant
Hoses/Clamps
(12 months)

Coolant
Flush/Replace (36 months) & 24 months/
48 000 km
(30,000
miles)
thereafter
O

Oil—Change
(6 months)
X X X
X X X
X X X X X
X X X X X X
X

Oil Filter—Replace (Every Oil Change)
X X X
X X X
X X
X X X
X
X X X X
X X

Drive Belts—Replace
As
Necessary
X X
X X X X

Air Filter—Replace
X X
X X

Air Filter—Clean (California Only) e

®

• •
Air
Filter
Canister—Clean
o o o
o

Fuel Filter—Service When Necessary

Injection
Pump
Timing & Engine Idle Speed—

Check
& Adjust
©

• 9 • • •
Underhood Rubber/Plastic Components—Inspect/Replace • • • • •

X
— All vehicles
O
— All
vehicles
except
California.
Recommended
for
California.
•
— California only.
Recommended
for all vehicles.

0 - 14
LUBRICATION
AND
MAINTENANCE

•
ENGINE
MAINTENANCE

INDEX

page
Air
Injection
Systems/Air Pump
. 17

Air-Conditioner
Compressor
21
Battery
19

Cooling System
15

Crankcase
Ventilation
System
17
Diesel Engine
Air Filter
Canister
17

Drive Belts
20
Engine
Air
Cleaner
Filter
Element
16

Engine Break-In
14

Engine
Oil 14

Engine
Oil
Change
and Filter
Replacement
15

Exhaust Gas
Recirculation
(EGR) System
...... 19
page
Exhaust
Manifold
Heat
Control
Valve
. 17
Exhaust System
, 21

Fuel System
18

Hoses
and
Fittings
16
Ignition
Cables,
Distributor
Cap and
Rotor
...... 19

Ignition
Timing
. 19

Oxygen
(02)
Sensor
19
Rubber/Plastic Components
20

Spark Plugs
. 19

Throttle
Control
Linkage
18

Vacuum Operated, Emission
Control
Components
19

ENGINE BREAK-IN
After first starting a new engine, allow it to idle
for 15 seconds before shifting into a drive gear. Also:
• Drive the vehicle at varying speeds less than 88
km/h (55 mph) for the first 480 km (300 miles).
• Avoid fast acceleration and sudden stops.
• Do not drive at full-throttle for extended periods of
time
• Do not drive at constant speeds
• Do not idle the engine excessively A special break-in engine oil is not required. The
original engine oil installed is a high quality lubri­
cant. New engines tend to consume more fuel and oil un­
til after the break-in period has ended.

ENGINE
OIL SPECIFICATIONS

API SERWICE
GRADE
Use an engine oil that conforms to API Service
Grade S5 SG/CD or SG/CE. MOPAR®provides engine
oils that conform to all of these service grades.

SULFATED ASH—DIESEL ENGINES
Oils that contain an excessive amount of sulfated
ash can cause deposits to develop on Diesel engine
valves. These deposits can result in valve wear.

SAE
WISC0SITY
An SAE viscosity grade is used to specify the vis­
cosity of engine oil. SAE 30 specifies a single viscos­
ity engine oil.
Engine oils also have multiple viscosities. 10W-30

<
5W-30

1
1 1

F
-20 0 10 20 32 60 80 100

C
-29 -18 -12 -7 0 16 27 38
ANTICIPATED
TEMPERATURE RANGE BEFORE
NEXT
OIL
CHANGE
J9000-39

Fig.
1 Temperature/Engine Oil Viscosity—Gasoline
Engines

-12°C
-18°C 10°F
0°F- 15W-40

-23°c(^-10eF

I
10W-30
WITH
WITHOUT
BLOCK HEATER
BLOCK
SYNTHETIC
OIL

HEATER
10W-30 5W-30

J9100-29

Fig.
2 Temperature/Engine Oil Viscosity—Diesel
Engines

ENERGY
G0NSERWING
OIL
An Energy Conserving type oil is recommended for
gasoline engines. They are designated as either EN­
ERGY CONSERVING or ENERGY CONSERVING

II.
OIL
LEVEL
INDICATOR (DIPSTICK)

GASOLINE ENGINES
The engine oil indicator is located at the right
front of the engine.

•

LUBRICATION
AND
MAINTENANCE
0 - 15
DIESEL
ENGINES

The Diesel engine oil level indicator is located at
the left center of the engine, above the
fuel
injection

pump (Fig. 3).

Fig.
3
Diesel
Engine
Oil
Dipstick

ACCEPTABLE
OIL
LEVEL
To maintain proper lubrication of an engine, the
engine oil must be maintained at an acceptable level.
For gasoline engines, the acceptable levels are indi­ cated between the ADD and
FULL
marks on oil
dip­
stick. For Diesel engines, the acceptable levels are
indicated between the L (low) and H
(high) marks
on
oil dipstick. The oil level should be checked periodically. The
vehicle should be on a level surface. Wait for
five
minutes after stopping the engine. For gasoline en­
gines,
add oil only when the level indicated on the
dipstick is at or below the ADD mark. For Diesel en­
gines,
add oil only when the level indicated on the
dipstick is between the L and H marks.
Never oper­
ate a Diesel
engine when
the oil
level
is below
the L mark. The distance between the L and H
marks represents 1.9L (2 Qts) engine oil.

CAUTION:
Do not
overfill
an
engine crankcase
with

oil. This
will
cause
oil
aeration
and
result
in a de­

crease
in the
engine
oil
pressure.
ENGINE
OIL
CHANGE AND FILTER REPLACEMENT

WARNING: PROTECTIVE CLOTHING
AND
GLOVES SHOULD
BE
WORN. EXPOSED SKIN SHOULD
BE

WASHED
WITH
SOAP
AND
WATER
TO
REMOVE
USED
ENGINE
OIL.
DO NOT
USE
GASOLINE, THIN­
NER,
OR
SOLVENTS
TO
REMOVE ENGINE
OIL

FROM
SKIN.
DO NOT
POLLUTE. DISPOSE
OF
USED
ENGINE
OIL
PROPERLY.
ENGINE
OIL
FILTER

All engines are equipped with a throw-away type
oil filter. The same type of filter is recommended
when the filter is changed.

OIL CHANGE
AND
FILTER
REPLACEMENT
Bring engine up to normal operating temperature.
A more complete drainage of oil will result.
(1) Remove the drain hole plug and drain the en­
gine oil from the crankcase.
(2) Install the drain hole plug with a replacement
gasket. For gasoline engines, the oil filter should be
replaced during every second engine oil change.
For Diesel engines, the oil filter should be re­
placed during every engine oil change.
(3) Rotate the oil filter counterclockwise to remove
it.
(4) Clean the engine cylinder block oil filter boss. (5) Apply a light coat of new engine oil to the rub­
ber seal on the oil filter.
(6) Install and hand tighten the oil filter 1/2 to 3/4
of a turn clockwise. (7) Add new engine oil at the fill hole location on
top of the engine cylinder head cover. Wipe off any spilled oil.
(8) Observe the oil level on the dipstick.

CAUTION:
Do not
overfill
the
engine crankcase
with

oil.
(9)
Start the engine. Observe the oil pressure
gauge or warning lamp (as applicable). If the oil
pressure does not increase, stop the engine immedi­ ately. Check oil level.

COOLING SYSTEM

WARNING:
USE
EXTREME CAUTION WHEN
THE
ENGINE
IS
OPERATING.
DO NOT PUT
YOUR
HANDS NEAR
THE
DRIVE BELT(S), PULLEYS
OR
FAN BLADE.
DO NOT
STAND
IN A
DIRECT LINE
WITH
THE FAN
BLADE.

INSPECTION SCHEDULE
Determine the coolant level. Inspect the cooling
system hoses/clamps after each service interval has
elapsed.

COOLANT LEVEL
It is recommended that the engine coolant level be
inspected at least once a month during periods of hot
weather.
With the engine at normal operating temperature,
check the coolant level in the coolant reserve tank.
The coolant level must be at least above the ADD mark. Add coolant to the coolant reserve tank only.

0-18
LUBRICATION
AND
MAINTENANCE

• MAINTENANCE SCHEDULE
A crankcase ventilation system must be clean to
provide good operation and durability. Periodic main­
tenance is necessary. Replace the PCV valve. Re­
move residual combustion deposits from the hoses and throttle body/intake manifold passages.
The PCV valve should be replaced and the system
should be serviced at the interval specified in main­
tenance schedule. If a vehicle is routinely used for short trips, the crankcase ventilation system could
possibly require more maintenance.
CRANKCASE AIR INLET FILTER
MAINTENANCE SCHEDULE Replace or clean, the air inlet filter at the interval
specified in maintenance schedule.
More frequent PCV system maintenance could be
required for:
• Vehicles routinely used for short trips
• Vehicles routinely involved in stop and go traffic
operation
• Vehicles routinely involved in extended periods of
engine idle
MAINTENANCE Clean and lubricate the crankcase air inlet filter
according to the following procedure. (1) Disconnect the fresh air hose from the port on
the crankcase air inlet filter housing (Fig. 8).
(2) Remove the air filter housing from the cylinder
head cover (Fig. 8). Clean the filter in kerosene or a similar solvent.
(3) Lubricate the filter by inverting the housing
and filling it with SAE 30 viscosity engine oil.
(4) Insert the air filter housing nipple in the cylin­
der head cover grommet. Connect the fresh air hose
to the upper port (Fig. 8).
J9000-52

Fig.
8
Crankcase
Air Inlet
Filter
THROTTLE CONTROL LINKAGE

Transmission linkage pivot pin areas (Fig. 9),
should be serviced. The areas lubricated every second
oil change with a multi-purpose lubricant (NLGI GC-
LB).

PIVOT
AREAS
Fig.
9
Transmission
Linkage
Pivot Areas

FUEL
SYSTEM

INSPECTION The fuel system filler cap, nozzle, tubes, hoses, and
connections should be inspected periodically.
FUEL FILTER The fuel filter requires service only when a fuel
contamination problem is suspected. For proper diag­
nosis and service procedures refer to Group 14, Fuel
System.
GASOLINE ENGINE FUEL REQUIREMENTS All gasoline engines require fuel that has a mini­
mum octane rating of 87 determined by the (R +
M)/2 calculation method.
The use of a brand of unleaded gasoline that con­
tains additives is recommended. Gasoline with addi­
tives will improve fuel economy and reduce emissions.

ALCOHOL/GASOLINE
BLENDS
Many brands of blended unleaded gasoline am now
available. Unleaded gasoline is blended with oxygenated-type
fuels to produce a clean air gasoline in many areas.
The use of this type of blended fuel is recommended.
ETH ANOL—Unleaded gasoline and ethanol
blended fuels are a mixture of 10 percent ethanol and 90 percent unleaded gasoline. This is an accept­
able blend of fuel.
MTBE— MTBE blended fuels are a mixture of un­
leaded gasoline and up to 15 percent MTBE (Methyl
Tertiary Butyl Ether). Unleaded gasoline blended
with MTBE is acceptable.

•

LUBRICATION
AND
MAINTENANCE
0 - 19 ETBE— This fuel is a mixture of unleaded gasoline
and up to 17 percent ETBE (Ethyl Tertiary Butyl

Ether).
Unleaded gasoline blended with ETBE is ac­ ceptable.
METHANOL—Do not use unleaded gasoline
blended with methanol. The use of this type of alco­ hol can result in engine performance and damage to
critical components. Engine problems that result
from the use of methanol possibly will not be covered by the new vehicle warranty.
Certain brands of unleaded gasoline contain a per­
centage of unidentified alcohol. These types of un­
leaded gasoline are not recommended.

ADDITIVES MIXED
WITH
GASOLINE
Use of fuel system cleaning additives should be
avoided. Many of these solutions could contain highly
active solvents. This type of solvent can be harmful
to the gasket and diaphragm material within the fuel system.

DIESEL
ENGINE FUEL REQUIREMENTS
All Diesel engines normally can use number 2D
Diesel fuel for most year-round operations. A fuel
conforming to ASTM Specification D-975 is recom­
mended. For extreme cold-weather operation (below
-18°C/0°F), or for prolonged cold-climate operation ei­
ther:
• Use No. ID fuel, or
• Add an equal quantity of kerosene to No. 2D fuel (a 50/50 mixture).
Both methods provide protection against fuel gel­
ling and waxing.
Diesel fuel seldom is without water contamination.
To help prevent fuel system malfunctions, drain all accumulated water from the separators periodically.

VACUUM OPERATED,
EMISSION
CONTROL
COMPONENTS

MAINTENANCE SCHEDULE
The following emission controls should be replaced
at the interval specified in the maintenance sched­

ule:

• Bi-level purge check valves
• Delay valves
• Heated air temperature sensor (HATS)
• Air cleaner vacuum motors

EXHAUST
GAS RECIRCULATION (EGR)
SYSTEM

MAINTENANCE SCHEDULE
Replace the EGR valve and tube, and clean the
passages at the interval specified in maintenance schedule. If necessary, refer to Group 25—Emission
Control Systems for additional information.
OXYGEN
(02)
SENSOR

MAINTENANCE SCHEDULE
Replace the 02 sensor at the interval specified in
maintenance schedule.

IGNITION
CABLES,
DISTRIBUTOR CAP AND

ROTOR

MAINTENANCE SCHEDULE
Replace the ignition cables, distributor cap, and ro­
tor at the interval specified in maintenance schedule.
Inspect the distributor for excessive wear and re­
place, as necessary. Refer to Group 8D—Ignition Sys­
tems for additional information.

IGNITION TIMING
MAINTENANCE SCHEDULE
Test and adjust, if necessary, the ignition timing at
the interval specified in maintenance schedule. Refer
to the specifications listed on the engine Emission Control Information label. Refer to Group 8D—Igni­
tion Systems and to Group 25—Emission Control Systems for additional service information.

SPARK
PLUGS MAINTENANCE SCHEDULE
Replace the spark plugs at the interval specified in
maintenance schedule. Refer to the Spark Plugs
chart below and to Group 8D—Ignition Systems for additional service information.

SPARK
PLUGS
ENGINE
SPARK

PLUG
SPARK

PLUG
GAP
TORQUE

3.9L
5.2L
5.9L
RN12YC

RN12YC

RN12YC
0.9 mm
(0.035
in.)
0.9 mm
(0.035
in.)
0.9 mm
(0.035
in.) 41 N*m (30 ft. lb.)
41 NVn (30 ft. lb.)
41 N*m (30 ft. lb.)

J9100-17

BATTERY

MAINTENANCE SCHEDULE
Replace battery at interval specified in mainte­
nance schedule.

i - 12
BRAKES

•
Fig.
6 integral Cylinder
Components

Cylinder Cleaning And Inspection Clean the cylinder body and cover with brake fluid
or brake cleaner only. Do not use any other type of solvents, or cleaning agent. Inspect the cylinder body and bore. Light discolor­
ation of the cylinder bore is normal and is an accept­
able condition. The bore should be smooth and free of
scores, scratches, corrosion and rust. Replace the cyl­
inder if the bore is worn, scored, or corroded.
Do not hone the bore in an attempt to restore the
surface finish. Replace the cylinder if the bore is
damaged in any way. Also replace the cylinder if the
body is cracked, porous, or the compensator port at
the bottom of each reservoir is blocked or damaged.
Inspect the cover and gasket. Replace the gasket if
distorted, cut, or torn. Replace the cover and retain­
ing wire if either component is distorted or damaged
in any way.
Do not reuse the old piston assemblies. Discard
these parts as soon as they are removed. Install re­
placement primary and secondary piston assemblies
only.

INTEGRAL
CYLINDER ASSEMBLY
(1) Coat cylinder bore and replacement piston as­
semblies with liberal quantity of clean brake fluid.
(2) Install secondary piston assembly in bore with
a turning motion. Do not use metal tools of any kind
to help ease piston into bore. Sharp edge tools will
scratch bore and cut piston seals.
(3) If cylinder is equipped with stop screw for sec­
ondary piston, press piston to bottom of bore and in­
stall screw.
(4) Install primary piston in bore.
(5) Press pistons inward with wood dowel and in­
stall piston snap ring. Be sure snap ring is fully
seated.
(6) Install new gasket on cover if necessary.
(7) Install cover retaining wire on cylinder if re­
moved. (8) Fill and bleed master cylinder on bench before
installing it in vehicle. Refer to following procedure.
BLEEDING
NEW
OR
OVERHAULED MASTER

CYLINDER
A new or overhauled master cylinder should be
purged of all air before installation on the vehicle. Cylinder bleeding is performed on the bench. Bleeding tools for the integral master cylinder in­
clude fabricated bleed tubes and a wood dowel.
Bleeding tools for the two-section master cylinder in­ clude bleed tubes C-4029 and a wood dowel (Fig. 7).

CYLINDER BLEEDING PROCEDURE
(1) Mount master cylinder assembly in vise.
(2) Attach bleed tubes to cylinder outlet ports and
insert tubes in reservoir fluid compartments (Fig. 7).
Bleed tubes can be fabricated from steel or copper
tubing and appropriate size fittings.
(3) Fill reservoir with fresh brake fluid. (4) Press cylinder pistons inward with wood dowel.
Then release pistons and allow them to return under spring pressure.
(5) Continue bleeding operations until air bubbles
are no longer visible in fluid.

Fig.
7 Master Cylinder
Bleeding—
Two-Section
Cylinder
Shown

MASTER
CYLINDER INSTALLATION
(1) Bleed master cylinder on bench before installa­
tion. (2) Position master cylinder on studs of power
brake unit. (3) Align power brake push rod with master cylin­
der piston. (4) Install and tighten cylinder attaching nuts to
23 N-m (200 in. lbs.). (5) Connect front and rear brakelines to cylinder.
Start brakeline fittings by hand. (6) Tighten brakeline fittings to 19 N«m (170 in.

lbs.).
(7) Bleed brakes.

5
- 32
BRAKES

•
CALIPER
OVERHAUL

CALIPER DISASSEMBLY (1) Drain
old
fluid
out of
caliper.
(2)
Pad
outboard shoe side
of
caliper interior with
a minimum
2.54 cm (1 in.)
thickness
of
shop towels (Fig.
12).
Towels will prevent piston damage when
piston comes
out of
bore.
(3) Remove caliper piston with short bursts
of
com­
pressed
air.
Apply
air
pressure through fluid inlet
port
of
caliper
(Fig. 12).

CAUTION:
Do
not
blow
the
piston
out of the
caliper.

This
practice
will
usually
result
in
severe piston
damage.
Use
only enough
air
pressure
to
ease
the
piston
out of the
bore.
In
addition,
do not
attempt
to

catch
the
piston
as it
leaves
the
caliper
bore. This
practice
will
result
in
personal
injury.
Fig.
12
Caliper Piston Removal
(4) Remove piston dust boot. Collapse boot with
screwdriver
or
punch
and
remove boot
(Fig. 13).

(5) Remove caliper piston seal with wood pencil
or

plastic tool
(Fig. 14). Do not use
metal tools
as
they could scratch piston bore.
CLEANING
AND
INSPECTION Clean
the
caliper components
(Fig. 15)
with Mopar
brake cleaner, fresh brake fluid,
or
denatured alcohol only.
Do not use
gasoline, kerosene, thinner,
or any
similar type
of
solvent. These products
can
leave
a

residue that
is
damaging
to
pistons
and
seals. Dry
the
caliper
and
piston with compressed
air or

allow them
to air dry. Do not use
rags
or
shop tow­

els.
Lint from such materials
can
adhere
to the
cali­
per
and
piston. Fig. 14 Removing Caliper Piston Seal
Inspect
the
caliper piston.
The
piston
is
made from
a phenolic resin (plastic material)
and
should
be

smooth
and
clean. Replace
the
piston
if
cracked
or
scored.
Do not
attempt
to
restore
a
scored piston
by

sanding
or
polishing.
The
piston must
be
replaced
if

damaged.
If
the
caliper piston must
be
replaced, install
the same
type
of
piston
in the
caliper.
Never
in­

terchange phenolic resin
and
steel
pistons.
The
piston seals,
seal
grooves,
caliper bore
and pis-

CLUTCH
6 - 1

CLUTCH

CONTENTS
page

CLUTCH
DIAGNOSIS
2

CLUTCH
COMPONENTS

MECHANICAL COMPONENTS
The clutch mechanism
in
AD
models with
a gas or

diesel engine consists
of a
single, dry-type clutch disc and
a
diaphragm style clutch cover.
A
hydraulic
linkage
is
used
to
engage/disengage
the
clutch disc
and cover.
The transmission input shaft
is
supported
in the

crankshaft
by a
bearing.
A
sleeve type release bear­
ing
is
used
to
operate
the
clutch cover pressure plate.
The release bearing
is
operated
by a
release fork
in

the clutch housing.
The
fork pivots
on a
ball stud
mounted inside
the
housing.
The
release fork
is
actu­ ated
by a
hydraulic slave cylinder mounted
in the

housing.
The
slave cylinder
is
operated
by a
clutch master cylinder mounted
on the
dash panel.
The
cyl­
inder push
rod is
connected
to the
clutch pedal.
The clutch disc
has
cushion springs
in the
disc
hub.

The clutch disc facing
is
riveted
to the hub. The
fac­ ing
is
made from
a
non-asbestos material.
The
clutch
cover pressure plate
is a
diaphragm type with
a one-

piece spring
and
multiple release fingers.
The
pres­ sure plate release fingers
are
preset during
manufacture
and are not
adjustable.
A
265 mm
clutch disc
and
cover
are
used
in
models
with
a 3.9L
engine.
A 280 mm
clutch disc
and
cover are used
in
models with
a 5.2L, or
5.9L engine.
A
330 mm
clutch disc
and
cover
are
used
in
models
equipped with
the
optional
5.9L
Cummins diesel
en­

gine.
Some diesel models
are
also equipped with
a

clutch pedal interlock switch.
The
switch
is in
circuit
with
the
starter relay
and is
actuated
by the
clutch
pedal
and
push
rod. The
clutch pedal must
be
fully depressed
in
order
to
start
the
engine.

HYDRAULIC LINKAGE COMPONENTS
The hydraulic linkage consists
of a
remote reser­
voir, clutch master cylinder, clutch slave cylinder and interconnecting fluid lines.
The clutch master cylinder
is
connected
to the

clutch pedal
and the
slave cylinder
is
connected
to

the clutch release fork.
The
master cylinder
is
mounted
on the
drivers' side
of the
dash panel adja­
cent
to the
brake master cylinder.
page

CLUTCH
SERVICE
11

CLUTCH LINKAGE FLUID
The clutch fluid reservoir, master cylinder, slave
cylinder
and
fluid lines
are
prefilled with fluid
at the

factory during assembly operations. The hydraulic system should
not
require additional
fluid under normal circumstances.
In
fact,
the
reser­
voir fluid level will actually increase
as
normal clutch wear occurs.
For
this reason,
it is
impor­
tant
to
avoid overfilling,
or
removing fluid from
the reservoir. If inspection
or
diagnosis indicates additional fluid
may
be
needed,
use
Mopar brake fluid,
or an
equiv­
alent meeting
SAE and DOT
standards J1703
and

DOT
3. Do not use any
other type
of
fluid.

CLUTCH
COMPONENT LUBRICATION
Proper clutch component lubrication
is
important
to satisfactory operation.
The
correct lubricant
and
not overlubricating
are
equally important. Apply rec­
ommended lubricant sparingly
to
avoid disc
and
pres­ sure plate contamination. Clutch
and
transmission components requiring
lu­

brication
are:
• pilot bearing
• release lever pivot ball stud
• release lever contact surfaces
• clutch disc
hub
splines
• clutch pedal pivot shaft bore
• clutch pedal bushings
• input shaft splines
• input shaft pilot
hub

• transmission front bearing retainer slide surface Do
not
apply grease
to any
part
of the
clutch
cover,
or
disc.

RECOMMENDED LUBRICANTS
Use Mopar multi-purpose grease
for the
clutch
pedal bushings
and
pivot shaft.
Use
Mopar high tem­
perature grease
(or
equivalent)
for all
other lubrica­
tion requirements. Apply recommended amounts
and
do
not
over lubricate.