
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.   

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.   

• 
BRAKES
 5 - 63 You must count the long flash along with the 
short flashes for an accurate fault code count. 
CLEARING
 A
 FAULT CODE 
 To clear a fault code, disconnect the control module 
connector or disconnect the battery for a minimum of 
five seconds. During system retest, wait 30 seconds 
to be sure the fault code does not reappear. 
FAULT 
CODE 
NUMBER 
 TYPICAL
 FAILURE
 DETECTED 
1 
 Not used. 
2 
 Open
 isolation valve wiring
 or
 bad control 
module. 
3 
 Open
 dump valve wiring
 or
 bad control 
module. 
4 
 Closed
 RWAL
 valve switch. 
5 
 Over 16 dump pulses generated
 in
 2WD 
vehicles (disabled
 for
 4WD). 
6  Erratic speed sensor reading while rolling. 
7  Electronic control module fuse
 pellet
 open, 
isolation output
 missing,
 or
 valve wiring 
shorted to ground. 
8 
 Dump
 output
 missing
 or
 valve wiring shorted
 to 
ground. 
9 
 Speed
 sensor wiring/resistance (usually high 
reading). 
10 
 Sensor
 wiring/resistance (usually
 low
 reading). 
11 
 Brake switch always on.
 RWAL
 light comes
 on 
when speed exceeds
 40
 mph. 
12  Not used. 
13  Electronic control module phase lock loop 
failure. 
14  Electronic control module program check 
failure. 
15  Electronic control module
 RAM
 failure. 
J9005-101 
Fig.
 8
 RWAL
 System
 Fault
 Codes  ANTILOCK COMPONENT SERVICE 
GENERAL SERVICE INFORMATION 
 The rear wheel antilock (RWAL) components are 
serviced as assemblies only. The module, hydraulic 
control valve, speed sensor and exciter ring are not 
repairable. These components must be replaced if di agnosis indicates a fault. 
HYDRAULIC VALVE REPLACEMENT  VALVE REMOVAL 
 (1) Raise vehicle. 
(2)
 Disconnect valve-to-sensor harness connector 
(Fig. 9).  (3) Disconnect brake lines connecting hydraulic 
valve to rear brakes and to combination valve. 
(4) Remove hydraulic valve attaching screws and 
remove valve from frame bracket (Fig. 9). 
VALVE INSTALLATION 
 (1) Start brake lines in hydraulic valve. 
(2)
 Position valve on frame bracket. (3) Install and tighten valve attaching nuts to 
22-34 N-m (16-25 ft. lbs.) torque.  (4) Tighten valve brake lines. 
(5)
 Bleed hydraulic valve and brakes. Refer to pro
cedure in Service Adjustments section. 
 (6)
 Lower vehicle. 
 J9005-112 
Fig.
 9
 RWAL
 Hydraulic
 Valve
 Attachment   

7 - 24
 COOLING SYSTEM 
• If the thermostat is being replaced, be sure that 
the replacement is the specified thermostat for the  vehicle model and engine type.  Factory installed thermostat housings on 3.9L/5.2L/ 
5.9L engines are installed on a gasket with an anti-
stick coating. This will aid in gasket removal and 
clean-up. 
(1) Disconnect negative battery cable at battery. 
(2) Drain cooling system until coolant level is be
low thermostat. Refer to Draining Cooling System in 
this group. If not equipped with air conditioning, pro ceed to step number 4. 
(3) If equipped with air conditioning: (a) Remove the support bracket (rod) located 
near the rear of generator (Fig. 28). 
 Fig.
 28
 Support
 Bracket—Generator
 Mounting 
Bracket-to-intake
 Manifold—
 Typical 
 (b) The drive belt must be removed. Refer to Belt 
Removal/Installation in the Engine Accessory 
Drive Belt section of this group. 
(c) The generator must be partially removed. Re
move the two generator mounting bolts. Do not re
move any wiring at generator. If equipped with 
4WD,
 unplug the 4WD indicator lamp wiring har
ness (located near rear of generator). 
(d) Remove generator. Position generator to gain 
access for thermostat gasket removal. 
(4) Remove upper radiator hose clamp. Special 
Clamp Tool number 6094 (Fig. 29) may be used to re
move the constant tension clamps. Remove upper ra
diator hose at thermostat housing. 
(5) Position the wiring harness (behind the ther
mostat housing) to gain access to thermostat hous ing. 
(6) Remove thermostat housing mounting bolts, 
thermostat housing, gasket and thermostat (Fig. 30).  Discard old gasket. 
 HOSE CLAMP HOSE 
J9207-36 
Fig.
 29
 Hose
 Clamp
 Tool 
 •THERMOSTAT 
MACHINED GROOVE 
J9207-14 
Fig.
 30 Thermostat—Gas
 Engines 
INSTALLATION-ALL GAS
 POWERED 
ENGINES 
 (1) Clean mating areas of intake manifold and 
thermostat housing.  (2) Install thermostat (spring side down) into re
cessed machined groove on intake manifold (Fig. 30). 
(3) Install gasket on intake manifold and over 
thermostat (Fig. 30). 
(4) Position the thermostat housing to the intake 
manifold. Note the word FRONT stamped on the 
housing (Fig. 31). For adequate clearance, this must 
be placed towards the front of vehicle. The housing  should be slightly angled forward after installation 
to intake manifold. 
(5) Install two housing-to-intake manifold bolts. 
Tighten bolts to 23 N-m (200 in. lbs.) torque.   

• 
COOLING
 SYSTEM
 7 - 35 
HOSE
 CLAMP  TOOL
 6094 
 HOSE 
CLAMP 
J9207-36 
 Fig.
 48
 Hose
 damp Tool 
TRANSMISSION
 OIL
 COOLER—EXCEPT DIESEL 
 The automatic transmission oil is cooled when it 
passes through a cooler in the radiator lower tank  (Fig. 49 and 50). 
h*-TRANSMISSION 
- OIL
 COOLER 
FRONT
 OF
 VEHICLE 
 AUTOMATIC 
TRANSMISSION 
 PRESSURE
 LINE 
6 AND
 8
 CYLINDER ENGINE 
RETURN
 LINE 
 RY402 
Fig.
 49 Top View of
 Transmission
 Oil
 Cooling 
 Circuit—Except Diesel—Typical 
COOLING
 TUBE  (CUT-A-WAY) 
DRAIN
 COCK 
 HOSE 
CLAMP 
 HOSE
 TO 
COOLER
 LINE 
 HOSE
 TO 
COOLER
 LINE 
RY401 
Fig.
 50 Automatic
 Transmission
 Oil Cooler—Except 
 Diesel—
 Typical 
In case of a leak in the transmission oil cooler, en
gine coolant may become mixed with transmission 
fluid or transmission fluid may enter engine cooling  system. Both cooling system and transmission should 
be drained and inspected in the event cooler is leak ing. 
 REPLACING
 OIL
 COOLER
 IN
 BOTTOM
 TANK 
Remove radiator. Refer to Radiator removal in this 
group. The servicing should be performed by a qual
ified repair facility. 
Once the repaired or replacement radiator has been 
installed, fill the cooling system and inspect for 
leaks.
 Refer to Refilling Cooling System and Testing  Cooling System For Leaks sections in this group. If 
the transmission operates properly after repairing 
the leak, drain the transmission and remove the 
transmission oil pan. Inspect for sludge and/or rust.  Inspect for a dirty or plugged inlet filter. If none of 
these conditions are found, the transmission and 
torque convertor may not require reconditioning. Re
fer to Group 21 for automatic transmission servicing. 
1RANSMISSI0N
 OIL
 COOLER-DIESEL 
 The transmission oil cooler is mounted to a bracket 
on the turbocharger side of the engine (Fig. 51). 
TRANSMISSION 
OIL 
COOLER 
 Fig.
 51 Automatic
 Transmission
 Oil Cooler—5.9L 
Diesel 
 REMOVAL 
In case of a leak in the transmission oil cooler, en
gine coolant may become mixed with transmission 
fluid or transmission fluid may enter engine cooling  system. Both cooling system and transmission should 
be drained and inspected in the event cooler is leak ing.  (1) Disconnect negative battery cable at battery. 
(2) Drain cooling system. Refer to Draining Cool
ing System.  (3) Disconnect coolant lines from cooler. 
(4) Disconnect transmission oil lines from cooler. 
Plug cooler lines to prevent oil leakage.  (5) Remove oil cooler mounting straps. 
(6) Lift oil cooler off of mounting bracket. 
INSTALLATION 
 (1) Position oil cooler on bracket. 
(2) Install mounting straps. 
(3) Connect transmission oil lines to cooler.   

8A
 - 12
 ELECTRICAL 
• 
ENGINE
 STARTER
 RELAY 
 STARTER RELAY CONNECTIONS 
GROUND SOLENOID  (85) TERMINAL 
 (87)  J928B-1 
RELAY OPERATION/TESTING 
OPERATION 
• The Battery terminal is connected to battery volt
age (B +
 )
 at all times. 
• The Solenoid terminal is connected to the battery 
terminal in the energized position which supplies 
battery voltage to the operated device.  • The Ignition terminal is connected to the electromag
net and usually connected to a switched power source. 
• The Ground terminal is connected to the electro
magnet and is usually grounded by a switch or PCM. 
TESTING 
 • Resistance value between the ground and ignition 
terminals (electromagnet) is
 75
 ±5 ohms for resistor 
relays and 86±5 ohms for diode relays. 
• Connect a battery to the ignition terminal and 
connect ground to the ground terminal. There should 
be continuity between the battery and solenoid ter minals (contact closed). 
ENGINE STARTER RELAY REPLACEMENT  The starter relay is located on the driver's side in
ner fender (Fig. 8). 
 PART THROTTLE
 A/C
 CLUTCH STARTER AUTO SHUT 
UNLOCK RELAY RELAY RELAY DOWN RELAY 
Fig.
 8
 Starter
 Relay 
(1) Replace the relay as required. 
(2) Test relay operation.  IGNITION SWITCH TEST 
After testing starter solenoid and relay and they 
check out okay, trouble is probably with ignition 
switch or its wiring.  Check all wiring for opens and shorts and connec
tions for being loose or corroded. 
BENCH TESTING STARTER SOLENOID  Refer to Group 8B - Battery Starter Service for 
starter removal procedures.  (1) Disconnect field coil wire from field coil termi
nal (Fig. 9). 
Fig.
 9 Field
 Coil
 Wire
 Terminal 
(2) Check for continuity between solenoid terminal 
and field coil terminal with a continuity tester. 
There should be continuity (Fig. 10). 
Fig.
 10 Continuity Test Between
 Solenoid
 Terminal 
 and
 Field
 Coil
 Terminal 
(3) Check for continuity between solenoid terminal 
and solenoid housing. There should be continuity 
(Fig. 11). 
 SOLENOID 
RR8BD33  Fig.
 11 Continuity Test Between
 Solenoid
 Terminal 
and Solenoid Case 
(4) If there is continuity solenoid is good. If there 
is no continuity in either test solenoid has an open 
circuit and is defective. Replace the starter motor.  (5) Install starter as described in Group 8B - Bat
tery Starter Service.  (6) Connect field coil wire to field coil terminal 
(Fig. 9).   

• BATTERY/STARTER/GENERATOR
 SERVICE
 8B - 1 
CONTENTS 
page page 
BATTERY
 SERVICE
 PROCEDURES
 1 SPECIFICATIONS 9 
GENERATOR
 SERVICE
 6 STARTER
 SERVICE
 PROCEDURES
 4 
BATTERY SERVICE PROCEDURES 
GENERAL
 INFORMATION  This section will cover the Battery service, re
moval, and installation procedures only. For diagnos
tic procedures, see Group 8A - Battery/Starting/  Charging Systems Diagnostics.  The Maintenance Free Battery (Fig. 1) does not 
have removable battery cell caps. Water can not be  added to this battery. The battery is sealed, except 
for small vent holes in the top. The chemical compo sition inside of the battery produces an extremely 
small amount of gases at normal charging voltages. 
The battery is equipped with a test indicator (Fig. 1) 
that display colored balls to indicate battery
 state-of-
 charge.  Green Indicator = Full charge 
Black Indicator = Discharged 
Yellow Indicator = Battery replacement required  Fig. 1 Maintenance Free Battery 
BATTERY
 VISUAL INSPECTION AND
 SERVICE 
 (1) Make sure ignition switch is on OFF position 
and all battery feed accessories are OFF.  (2) Disconnect and remove battery cables at bat
tery. Remove NEGATIVE cable first. 
 WARNING: WEAR
 A
 SUITABLE PAIR
 OF
 RUBBER 
GLOVES
 (NOT THE
 HOUSEHOLD TYPE) WHEN
 RE
 MOVING
 A
 BATTERY
 BY
 HAND. SAFETY
 GLASSES 
SHOULD ALSO
 BE
 WORN.
 IF THE
 BATTERY
 IS 
CRACKED
 OR
 LEAKING
 THE
 ELECTROLYTE
 CAN 
 BURN
 THE
 SKIN
 AND
 EYES. 
(3) Remove battery hold down (Fig. 2) and remove 
battery from vehicle.  Fig. 2 Battery
 Holddown 
BATTERY/STARTER/GENERATOR
 SERVICE   

8B
 - 6
 BATTERY/STARTER/GENERATOR
 SERVICE 
• 
GENERATOR SERVICE 
CONTENTS 
page 
GENERATOR
 REPLACEMENT-
 DIESEL
 ENGINE
 8 
GENERAL
 INFORMATION
 6 
GENERAL
 INFORMATION  This section will cover generator removal
 and in
stallation.
 The
 generator
 is not
 serviceable. Informa
tion covering on-vehicle testing
 can be
 found
 in 
 Group
 8A -
 Battery/Starting/Charging/System Diag
nostics.  The standard equipment generator
 on the D and W 
bodies
 is the 75 amp
 generator.
 The
 Ramcharger
 is 
 equipped with
 the 90 amp
 generator. When
 a
 vehicle 
is equipped with
 a
 heavy duty package
 or
 diesel
 en
gine,
 a 120 amp
 generator
 is
 used. 
GENERATOR
 REPLACEMENT
 -3.9L/5.2L/5.9L-LDC 
GAS
 ENGINE 
Drive belts
 on
 these engines
 are
 equipped with
 a 
spring loaded automatic belt tensioner
 (Fig. 1).
 This 
belt tensioner
 is
 used
 on all
 belt configurations.
 For 
 more information, refer
 to
 Group
 7 -
 Cooling, Belt 
Removal/Installation. 
REMOVAL 
 (1) Disconnect negative cable from battery. 
(2) Attach
 a
 socket/wrench
 to
 pulley mounting bolt 
of automatic tensioner
 (Fig. 1). 
(3) Rotate tensioner assembly clockwise
 (as
 viewed 
from front) until tension
 has
 been relieved from belt.  (4) Remove belt from idler pulley first. 
(5) Remove belt from vehicle. 
(6)
 Remove lower generator mounting bolt
 and nut 
(Fig.
 2). 
(7) Remove upper generator mounting bolt
 and re
move generator. 
(8) Remove
 B+
 terminal
 nut, 2
 field terminal 
nuts,
 ground,
 and
 harness hold down nuts
 (Fig. 3). 
Remove wire connectors. 
INSTALLATION 
 (1) Install harness
 to
 generator. Tighten nuts
 as 
follows: 
• Ground terminal,
 B+
 terminal
 and
 Wire Harness  Hold Down
 7-10 N*m
 (60-90
 in.
 lbs.). 
• Field terminals
 2.5-3 N-m
 (20-30
 in.
 lbs.).  (2) Install generator. Tighten both bolts
 to 41 N»m 
(30
 ft.
 lbs.). 
 page 
GENERATOR
 REPLACEMENT—3.9L/5.2L/ 
 5.9L-LDC
 GAS
 ENGINE
 6 
GENERATOR
 REPLACEMENT—5.9L
 HDC-GAS 
 ENGINE
 7 
 Fig.
 1 Automatic Belt Tensioner—Belt
 Removal/ 
Installation 
Fig.
 2
 Generator
 Mounting
 Bolts