1993 DODGE TRUCK Service Repair Manual

13
- 30 FRAME AND BUMPERS
ATTACHED COMPONENTS

SKID
PLATES
TRANSFER CASE SKID
PL
ATF
4 WD
VEHICLES

REMOVAL
(1) Position
a
support under
the
skid plate.
(2) Remove
the
bolts that attach
the
skid plate
to

the frame crossmember. Remove
the
bolts
for the

crossmember support
to the
frame rail.
(3) Remove
the
crossmember support
and the
skid
plate.

INSTALLATION
(1) Position
and
support
the
skid plate
and the

crossmember support
at the
frame rail. Align
the

bolt holes.
(2) Insert
the
bolts through
the
frame crossmember
and frame rail. Install
the
nuts. Tighten
to 23 N*m

(200
in. lbs.)
torque.
(3) Remove
the
support from under
the
skid plate.
Fig.
1
Transfer
Case Skid
Plate—4WD Vehicles
FUEL TANK SKID
PLATE-4WD
VEHICLES
REMOVAL

(1) Position
a
support under
the
fuel tank skid
plate.
(2) Remove
the
nuts
and
bolts that attach
the
skid
plate
to the
frame rails, rear crossmember
and the
support bracket.
(3) Remove
the
skid plate from
the
fuel tank
and

the vehicle.

INSTALLATION
(1) Position
and
support
the
skid plate under
the

fuel tank. Insert
the
studs
in the
support bracket.
(2) Install
the
nuts
to
attach
the
skid plate
to the

support bracket. Install
the
bolts
at the
rear cross- member. Install
the
bolts
at the
frame side rails.
Tighten
the
nuts
and
bolts
to 23 N*m (200 in. lbs.)

torque.
(3) Remove
the
support from under
the
skid plate.
FRAME FRAME

Fig.
2
Fuel
Tank
Skid
Plate-4WD Vehicles

SPARE
TIRE/WHEEL
CARRIER
REMOVAL
(1) Remove
the nut and
insert from
the
support
rod. (2) Lower
the
hanger
and
remove
the
spare tire/
wheel from
the
underside
of the
frame crossmember.
(3) Remove
the
retaining
nut,
lockwasher
and

hanger from
the
left frame rail.
(4) Refer
to
removal procedures
for
installation. BOLT BOLT FRAME

Fig.
3
Spare
The/Wheel Carrier

1
•

FRAME
AND
BUMPERS
13 - 31 PIVOT BOL T ADJUSTMENT
(1) Refer to the Pivot Bolt Height chart and deter­
mine the length of dimension A for the pivot bolt.
PIVOT BOLT HEIGHT
PIVOT BOLT HEIGHT
RIM SIZE TIRE SIZE BOLT HEIGHT
15 x 6.5 P195/75R-15
4.0"
P205/75R-15 4.0"
P235/75R-15XL
5.0"

15
x 7.0
P235/75R-15XL 5.2"

10R-15LT-B
5.62"

16 x 6.0 7.50-16 SINGLE & DUAL
6.75"

LT215/85R-16 SINGLE
4.5"

LT215/85R-16 DUAL 5.0"

LT235/85R-16
5.0"
16.5 x 6.0 8.00-16.5 SINGLE
4.12"

8.00-16.5 DUAL
5.0"

16.5 x 6.75 8.75-16.5 5.0"
NOTE: 7.50 x 16 TIRE SHOULD BE INSTALLED IN A DISH
UP POSITION ONLY
(2) Loosen the pivot bolt nut and adjust dimension
A to required length.
INSTALLATION (1) Position the hanger under the frame side rails
and insert the pivot bolt in the frame rail hole. (2) Install the lockwasher and the nut on the pivot
bolt. Tighten the nut to 61 N*m (45 ft. lbs).
(3) Position the spare tire/wheel on the hanger.
Raise the hanger and insert the support rod in the

hole.

(4) Install the washer,nut and insert on the sup­
port rod. Tighten the nut to 11 Nnn (95 in. lbs.).

CAB

REMOVAL
The cab is attached to the frame with holddowns

(Figs.
4 and 5). The cab can be removed for repair or
service. Refer to the associated component procedure
when necessary.
(1) Disconnect the battery cables from the termi­

nals.
Remove the battery from the tray.
(2) Disconnect the wire harness connectors from
the engine components. Disconnect from the frame. (3) Disconnect the parking brake cable and the
brake lines. (4) Disconnect the engine controls.

(5)
Disconnect the heater and A/C hoses.
(6) Disconnect the cable from the starter motor.

(7)
Disconnect the transmission and transfer case
(if equipped) shift linkage. (8) Disconnect the tubing from the clutch master
cylinder (if equipped). (9) Disconnect the steering shaft from the steering
gear. (10) Disconnect all remaining connections between
the cab and the frame components. (11) Remove the restraint cable from the cab.
(12) Remove the cab front holddown nuts and
washers (Fig. 4). The nuts are accessible at the front,
underside of the cab.
(13) Remove the cab holddown bolts (Fig. 5). The
bolts are accessible from the underside of the cab.
(14) Separate and remove the cab from the frame.

BOLT
Fig.
4 Front Cab
Holddown

CAB
FRONT DOWN HOLD
CAB
REAR DOWN HOLD
J9113-18

Fig.
5 Cab Holddowns—Typical

13
- 32
FRAME
AND
BUMPERS

• r INSTALLATION
(1) Verify the insulators and spacers are positioned
on the frame holddown brackets (Figs. 4 and 5). (2) Position the cab on the frame.
(3) Install the cab holddown nuts and bolts (Figs. 4
and 5). Tighten the nuts to 68 N-m (50 ft. lbs.)
torque. Tighten the bolts to 81 Nnn (60 ft. lbs.)
torque. (4) Position the restraint cable ends on the cab
rear seat belt anchor bolts. Install the retaining nuts.
Tighten the nuts to 45 N-m. (33 ft. lbs.) torque.
(5) Connect the steering shaft to the steering gear.
(6) Connect the tubing to the clutch master cylin­
der (if equipped).
(7) Connect the transmission and transfer case (if
equipped) shift linkage. (8) Connect the cable to the starter motor.
(9) Connect the heater and A/C hoses.
(10) Connect the engine controls.
(11) Connect the parking brake cable and the
brake lines.
(12) Connect the wire harness connectors to the
engine components and to the frame. (13) Connect all remaining items between the cab
and the frame components. (14) Install the battery in the tray. Connect the ca­
bles to the terminals. (15) Inspect the installation of the cab on the
frame and verify that:
• All connecting hardware is tightened
• All fluids and lubricants are full
• All electrical, engine, drivetrain and chassis com­
ponents are operational.

CARGO
BOX REMOVAL The cargo box is attached to the rear frame struc­
ture with holddown bolts (Fig. 6). The box can be re­ moved for repair or service access. Refer to the
associated component procedures when necessary.
(1) Disconnect the battery cables from the termi­

nals.

(2) Disconnect the rear lamp wire harness connec­

tors.
(3) Support the exhaust pipe. Disconnect the sup­
port hanger from the cargo box. (4) Loosen the clamps. Disconnect the fuel and
vent hoses from the nozzle tubes (Fig. 7). (5) Remove the cargo box holddown bolts (Fig. 6).
The bolts are accessible from the underside of the cargo box. (6) Identify, mark and retain the spacers (if used)
for installation reference. (7) Remove the cargo box from the frame (Fig. 6).

CARGO CARGO
BOX

FWD HOSE CLAMP
J9123-551
Fig.
7
Fuel
& Vent
Hoses
INSTALLATION
(1) Position cargo box on the frame (Fig. 6).
(2) Insert the spacers. Install the holddown bolts
(Fig. 6). Tighten the bolts to 47 Nnn (35 ft. lbs.)
torque.
(3) Connect the fuel and vent hoses to the nozzle
tubes (Fig. 7). Tighten the fuel hose clamp screw to 3
Nnn (20 in. lbs.) torque. Tighten the vent hose clamp screw to 2 Nnn (14 in. lbs.) torque.
(4) Connect the tail pipe to the hanger on the
cargo box. Remove the support. (5) Connect rear lamp wire harness connectors.
(6) Connect the battery cables to the terminals.
(7) Inspect the installation of the cargo box on the
frame and verify that:
• All connecting hardware is tightened • All electrical system components are operational

•

FUEL
SYSTEM
14 - 1

FUEL
SYSTEM

page

ACCELERATOR
PEDAL
AND THROTTLE
CABLE
................ 25

DIESEL
FUEL
INJECTION-COMPONENT
DESCRIPTION/SYSTEM
OPERATION
76

DIESEL
FUEL
INJECTION-GENERAL

DIAGNOSIS
88

DIESEL
FUEL
INJECTION-SERVICE

PROCEDURES
....................... 106

FUEL
DELIVERY
SYSTEM-EXCEPT
DIESEL
.. 3

FUEL
DELIVERY-DIESEL
ENGINE
15

FUEL
TANKS
.... 20
page

GENERAL
INFORMATION 1

MULTI-PORT
FUEL
INJECTION (MPI)-
COMPONENT
DESCRIPTION/SYSTEM

OPERATION-EXCEPT
DIESEL
29

MULTI-PORT
FUEL
INJECTION (MPI)-
COMPONENT
REMOVAL/INSTALLATION-

EXCEPT
DIESEL
64

MULTI-PORT
FUEL
INJECTION (MPI)-
GENERAL
DIAGNOSIS-EXCEPT
DIESEL
...43

SERVICE
ADJUSTMENTS-DIESEL
122

SPECIFICATIONS
123

GENERAL INFORMATION

Throughout this group, references are made to par­
ticular vehicle models by alphabetical designation or
by the particular vehicle nameplate. A chart showing a breakdown of the alphabetical designations is in­
cluded in the Introduction section at the beginning of
this manual.
The 5.9L (V-8) gas powered engine will be referred
to in this group as either the: LDC (Light Duty Cy­ cle) or HDC (Heavy Duty Cycle) engine. The HDC engine can be easily identified by the use of an en­
gine mounted air injection pump. The 3.9L/5.2L/5.9L
LDC engine will not use an air injection pump.
This Fuel System group will cover all fuel system
components for the 3.9L (V-6), 5.2L (V-8), 5.9L LDC
(V-8),
5.9L HDC (V-8) and 5.9L (in-line six cylinder)
diesel engines.
The Fuel System consists of: the fuel tank, an
electric (fuel tank mounted) fuel pump and fuel fil­
ter. It also consists of fuel tubes/lines/hoses, vacuum

hoses,
throttle body and fuel injector(s).
The Fuel Delivery System consists of: the electric
fuel pump, fuel filter, fuel tubes/lines/hoses, fuel rail,
fuel injectors and fuel pressure regulator.
A Fuel Return System is used on all vehicles (all
engines) except the 5.9L (V-8) gas powered engine. On this engine, a returnless type fuel system is
used. The fuel return system consists of fuel tubes/
lines and hoses that route fuel back to the fuel tank.
The Fuel Tank Assembly consists of: the fuel
tank, filler tube, fuel gauge sending unit/electric fuel
pump module, a pressure relief/rollover valve and a
pressure-vacuum filler cap. Also to be considered part of the fuel system is the
Evaporation Control System. This is designed to
reduce the emission of fuel vapors into the atmo­ sphere. The description and function of the Evapora­
tive Control System is found in Group 25, Emission Control Systems.

FUEL
USAGE
STATEMENT-GAS
ENGINES
Your vehicle was designed to meet all emission
regulations and provide excellent fuel economy using
high quality unleaded gasoline. Only use unleaded gasolines having a minimum posted octane of 87. If your vehicle develops occasional light spark
knock (ping) at low engine speeds, this is not harm­

ful.
However, continued heavy knock at high speeds can cause damage and should be re­
ported to your dealer immediately. Engine dam­ age as a result of heavy knock operation may not be
covered by the new vehicle warranty. In addition to using unleaded gasoline with the
proper octane rating, those that contain deter­

gents,
corrosion and stability additives are rec­
ommended. Using gasolines that have these additives will help improve fuel economy, reduce
emissions and maintain vehicle performance. Gener­ ally, premium unleaded gasolines contain more addi­
tive than regular unleaded gasolines. Poor quality gasoline can cause problems such as
hard starting, stalling and stumble. If you experience
these problems, use another brand of gasoline before considering service for the vehicle.

14
- 2
FUEL SYSTEM

•
GASOLINE/OXYGENATE
BLENDS

Some fuel suppliers blend unleaded gasoline with
materials that contain oxygen such as alcohol, MTBE and ETBE. The type and amount of oxygenate used
in the blend is important. The following are gener­
ally used in gasoline blends:

ETHANOL
Ethanol (Ethyl or Grain Alcohol) properly blended,
is used as a mixture of 10 percent ethanol and 90
percent gasoline. Gasoline with ethanol may be
used in your vehicle.

METHANOL

CAUTION:
DO NOT USE
GASOLINES CONTAINING
METHANOL.
Use of methanol/gasoline blends may re­
sult in starting and driveability problems. In addition,
damage may be done to critical fuel system compo­
nents.

Methanol (Methyl or Wood Alcohol) is used in a va­
riety of concentrations blended with unleaded gaso­
line.
You may encounter fuels containing 3 percent
or more methanol along with other alcohols called co-
solvents.
Problems that are the result of using methanol/gas­
oline blends are not the responsibility of Chrysler Corporation. They may not be covered by the vehicle
warranty.

MTBE/ETBE
Gasoline and MTBE (Methyl Tertiary Butyl Ether)
blends are a mixture of unleaded gasoline and up to 15 percent
MTBE.
Gasoline and
ETBE
(Ethyl
Ter­

tiary Butyl Ether) are blends of gasoline and up to 17 percent ETBE. Gasoline blended with MTBE or
ETBE may be used in your vehicle.

CLEAN
AIR GASOLINE Many gasolines are now being blended that con­
tribute to cleaner air, especially in those areas of the
country where air pollution levels are high. These
new blends provide a cleaner burning fuel and some are referred to as Reformulated Gasoline.
In areas of the country where carbon monoxide lev­
els are high, gasolines are being treated with oxy­
genated materials such as MTBE, ETBE and ethanol.
Chrysler Corporation supports these efforts toward
cleaner air and recommends that you use these gas­
olines as they become available.

FUEL
REQUIREMENTS-DIESEL ENGINE
Use good quality diesel fuel from a reputable sup­
plier in your Chrysler Corporation vehicle. For most
year-round service, number 2 (two) diesel fuel meet­ ing ASTM specification D-975 will provide good per­
formance. If the vehicle is exposed to extreme cold (below -18°C - 0°F), or for any reason is required to
operate at colder than normal conditions for pro­ longed periods, then dilution of the 2D fuel with 50
percent kerosine or number ID diesel fuel will pro­
vide better protection from fuel gelling or wax-plug­ ging of the fuel filters. Diesel fuel is seldom
completely free of water. To prevent fuel system
trouble, including fuel tube (line) freezing in winter, drain the accumulated water using the drain pro­
vided. If you buy good quality fuel and follow the cold weather advice above, fuel conditioners should
not be required in your vehicle.

•

FUEL SYSTEM
14 • 3
FUEL
DELIVERY SYSTEM-EXCEPT DIESEL

INDEX
page
Fuel Filter—3.9L/5.2L Gas Engine
............
10

Fuel
Filter—5.9L
Gas Engine
11
Fuel Pressure Leak Down Test—3.9L/5.2L Engine
. 8

Fuel Pressure Leak Down Test—5.9L Engine
.... 9

Fuel Pump Capacity
Test—All
Gas
Engines
..... 8

Fuel Pump
Control
........................
5

Fuel Pump Module—3.9L/5.2L Engines
3

GENERAL INFORMATION
Two different types
of
fuel delivery/fuel return sys­
tems
are
used.
The
system used with
the
3.9L/5.2L
engine will route excess fuel pressure back
to the

fuel tank through
a
fuel return line.
The
system used
with
the 5.9L
engine will
not
have
a
separate fuel
re­

turn line. This system will
be
referred
to as a re-

turnless type.
The
fuel pump module used with
the
5.9L engine will contain
a
combination fuel pressure
regulator
and
fuel filter. Refer
to the
following Fuel
Pump Module
for
additional information
or,
refer
to

the Multi-Port Fuel Injection sections
of
this Fuel System group. A separate frame mounted fuel filter will
not be

used with
any 5.9L gas
powered engine.

FUEL
PUMP
M0DULE-3.9L/5.2L
ENGINES
The fuel pump module
on
vehicles equipped with
3.9L/5.2L engines
is
installed
in the top of the
fuel
tank (Fig.
1). The
fuel pump module contains
the
fol­ lowing components (Fig.
2):

• Fuel pump
• Fuel pump reservoir
•
A
separate in-tank fuel filter
• Pressure relief/rollover valve
PRESSURE
RELIEF/
PUMP/GAUGE

Fig.
1
Top View
of
Fuel
Pump
Module—3.9U5.2L
Engine
page
Fuel Pump Module—5.9L Engine
.............
3

Fuel System Pressure Release
...............
5

Fuel System Pressure Test—3.9L/5.2L Engine
... 5
Fuel System Pressure Test—5.9L Engine
7

Fuel Tubes/Lines/Hoses
and
Clamps
..........
11

General
Information
3

Quick-Connect
Fittings
11

• Fuel pump gauge sending unit
• Fuel supply
and
return tube connections
J9114-147

Fig.
2
Fuel
Pump
Module
Components—Typical

FUEL PUMP MODULE—5.9L ENGINE
The fuel pump module
on
vehicles equipped with
a

5.9L
gas
powered engine
is
installed
in the top of
the
fuel tank
(Fig. 3). The
fuel pump module contains
the following components (Fig.
2):
• Fuel filter/fuel pressure regulator
• Fuel pump • Fuel pump reservoir
•
A
separate in-tank fuel filter
• Pressure relief/rollover valve
• Fuel pump gauge sending unit
• Fuel supply tube connection

14-4
FUEL
SYSTEM

•

Fig.
3 Top View of
Fuel
Pump
Module—5.9L
Engine
FUEL
PUMP

The fuel pump used in this system has a perma­
nent magnet electric motor. The pump is part of the
fuel pump module (Fig. 2). The fuel pump module is suspended in fuel in the fuel tank. Fuel is drawn in
through a filter and pushed through the electric mo­
tor to the outlet. The pump contains a check valve.
This valve is located near the pump outlet. It re­ stricts fuel movement in either direction to maintain
fuel supply line pressure when the pump is not oper­ ational. Voltage to operate the pump is supplied
through the auto shut down (ASD) and fuel pump re­
lays.

WARNING:
THE
FUEL SYSTEM
IS
UNDER
A
CON­ STANT PRESSURE (EVEN
WITH
THE
ENGINE OFF).
BEFORE
SERVICING
THE
FUEL PUMP, FUEL

TUBES
(LINES), FUEL FILTER,
OR
FUEL
INJEC­

TOR^),
THE
FUEL SYSTEM PRESSURE MUST
BE
RELEASED.

FUEL
PUMP
REPLACEMENT

The fuel pump is not serviceable. If the fuel pump
needs replacement, the complete fuel pump module must be replaced. Perform the Fuel System Pressure
Release procedure before servicing the fuel pump.

FUEL
PUMP
MODULE
REMOVAL

WARNING:
THE
FUEL SYSTEM
IS
UNDER
A
CON­ STANT PRESSURE (EVEN
WITH
THE
ENGINE OFF).
BEFORE
SERVICING
THE
FUEL PUMP MODULE,
THE FUEL SYSTEM PRESSURE MUST
BE RE­
LEASED.

CAUTION:
Whenever
the
fuel
pump
module
is
ser­
viced,
the
locknut
and gasket
must
be replaced. (1) Drain the fuel tank. Refer to Draining Fuel
Tank in the Fuel Tank section of this group.
(2) Remove fuel tank. Refer to the Fuel Tank sec­
tion of this group.
(3) The fuel pump module locknut is threaded onto
the fuel tank. Remove the fuel pump module locknut
(Figs.
1 or 3). The fuel pump module will spring up
when the locknut is removed.

(4)
Remove module from fuel tank.

DISASSEMBLY-
FUEL GAUGE SENDING
UNIT
(1) Remove sending unit mounting screws (Fig. 4).
(2) Mark the sending unit electrical wires before

FUEL
GAUGE
TABS

IN-TANK

FUEL
FILTER
J9114-146

Fig.
4
Module
Service—Typical
removal for correct installation. Carefully disconnect electrical wires from sending unit. Remove sending unit.
(3) Reverse order of removal for installation.

IN-TANK FUEL FILTER
The in-tank filter is attached to the bottom of the
fuel pump module (Fig. 4).
(1) Pry the mounting tabs back and remove the in-
tank fuel filter.
(2) Install new fuel filter into retaining tabs.

FUEL
PUMP
MODULE
INSTALLATION

CAUTION:
Whenever
the
fuel
pump
module
is
ser­
viced,
the
locknut
and
gasket must
be
replaced.

(1) Using a new gasket, position fuel pump module
into opening in fuel tank. (2) Position new locknut over top of fuel pump
module. (3) Tighten locknut. (4) Install fuel tank. Refer to Fuel Tank Installa­
tion in this section.

•

FUEL SYSTEM
14-5
FUEL PUMP CONTROL

The powertrain control module (PCM) computer en­
ergizes the fuel pump through the automatic shut
down (ASD) and fuel pump relays. Battery voltage is applied to the relay from the ignition switch. The coil
in the relay is energized when a ground is provided
by the PCM. The relays are located in the engine compartment (Fig. 5).

DATA
UNK
CONTROL

CONNECTOR
MODULE
J9314-164

Fig.
5
Fuel
Pump
and ASD
Relays

FUEL
SYSTEM
PRESSURE
RELEASE

ALL
GAS
ENGINES
The fuel system is under constant fuel pressure
(even with the engine off).
WARNING: BECAUSE THE FUEL SYSTEM IS UN­ DER CONSTANT FUEL PRESSURE, THIS PRES­
SURE MUST BE RELEASED BEFORE SERVICING
ANY FUEL SUPPLY OR FUEL RETURN SYSTEM COMPONENT. THIS DOES NOT APPLY TO THROT­
TLE BODY REMOVAL.
(1) Disconnect negative battery cable.
(2) Remove the fuel tank filler tube cap to release
fuel tank pressure. (3) Remove protective cap from pressure test port
on the fuel rail (Figs. 6, 7 or 8).
WARNING: DO NOT ALLOW FUEL TO SPILL ONTO
THE ENGINE INTAKE OR EXHAUST MANIFOLDS. PLACE SHOP TOWELS UNDER AND AROUND THE
PRESSURE PORT TO ABSORB FUEL WHEN THE
PRESSURE IS RELEASED FROM THE FUEL RAIL.
WARNING: WEAR PROPER EYE PROTECTION
WHEN RELEASING FUEL SYSTEM PRESSURE.
(4) Obtain the fuel pressure gauge/hose assembly
from fuel pressure gauge tool set 5069. Remove the
gauge from the hose.
CONNECTOR
HOSES
J9214-27

Fig.
7
Fuel
Pressure
Test Port—5.2L (V-8)
Engine
(5) Place one end of hose (gauge end) into an ap­
proved gasoline container. (6) Place a shop towel under the test port.
(7) To release fuel pressure, screw the other end of
hose onto the fuel pressure test port.
(8) After fuel pressure has been released, remove
the hose from the test port. (9) Install protective cap to fuel test port.

FUEL SYSTEM
PRESSURE
TEST-3.9L/5.2L

ENGINE
Fuel systems on vehicles equipped with a 3.9L or