2003 DODGE RAM service

(17) Fabricate 51 mm (2.0 in.) long repair inserts
using scrap from the old structure or the replacement
part. It will be necessary to split the inserts on each
of their four sides to fit into the hydroform.
(18) Remove any paint or e-coat from the inserts
and also to the interior and exterior of the hydro-
forms.
(19) Cut plug weld holes as described below.
²On the upper rail, cut one 13 mm (0.5 in.) hole
on each side of the rail, 25 mm (1.0 in.) from the butt
joint of the tubes.
²On the lower rail, cut one 13 mm (0.5 in.) hole
on the top and bottom sides of the rail 25 mm (1.0
in.) from the butt joint of the tube.
²On the lower rail, cut two 13 mm (0.5 in.) holes
on the inner and outer sides of the rail 25 mm (1.0
in.) from the butt joint of the tube.
CAUTION: Shield the surrounding area and compo-
nents from exposure to the welding spatter and
heat.
(20) Install the insert 1º into the replacement part
and tack into place with a weld.
(21) Insert the service part into place and using
the appropriate measuring equipment, verify thefront end sheet metal bracket's location in all three
(X,Y, and Z) planes of space. (Fig. 20)
(22) Complete all 360É plug welds.
NOTE: Before the final welding, use three dimen-
sional measuring equipment to ensure the part is in
the correct location. Verify that tap plate extrusion
at the bottom of the vertical post lines up with the
isolator and hole in the frame perch mount. Also
ensure the lower radiator closure tube is bolted into
the forward shotgun ends.
(23) Complete welding by making a 360É butt weld
around the fender rails.
(24) Metal finish the exposed welds on the hydro-
forms.
(25) Dress the welded area and apply corrosion
resistant coatings inside and out.
(a) Inside the rail, inject a creeping wax based
rust inhibitor compound to the inside of the hydro-
forms ensuring 100% coverage including the mat-
ing face between the fender rail sections and insert
such that corrosion protection is restored in the
internal cavity.
(b) Apply a durable top coat to the outside of the
repair area.
Fig. 19 HYDROFORM FENDER RAILS
1 - HYDROFORM FENDER RAIL
2 - FRONT END SHEET METAL BRACKET
3 - UPPER RADIATOR CROSSMEMBER BOLTS (4)4 - UPPER RADIATOR CROSSMEMBER
5 - LOWER RADIATOR CROSSMEMBER BOLTS (8)
6 - LOWER RADIATOR CROSSMEMBER
DRFRAMES & BUMPERS 13 - 13
FRAME (Continued)

STANDARD PROCEDURE - REAR FRAME
H-SECTION REPLACEMENT
SAFETY PRECAUTIONS AND WARNINGS
WARNING: USE EYE PROTECTION WHEN GRIND-
ING OR WELDING METAL, SERIOUS EYE INJURY
CAN RESULT.
²BEFORE PROCEEDING WITH FRAME REPAIR
INVOLVING GRINDING OR WELDING, VERIFY THAT
VEHICLE FUEL SYSTEM IS NOT LEAKING OR IN
CONTACT WITH REPAIR AREA, PERSONAL INJURY
CAN RESULT.
²DO NOT ALLOW OPEN FLAME OR HEAT AND
METAL SPATTER FROM ARC WELDING, TO CON-
TACT PLASTIC BODY PANELS. FIRE OR EXPLO-
SION CAN RESULT.
²WHEN WELDED FRAME COMPONENTS ARE
REPLACED, ENSURE COMPLETE PENETRATION
WELD IS ACHIEVED DURING INSTALLATION. IF
NOT, DANGEROUS OPERATING CONDITIONS CAN
RESULT.
²STAND CLEAR OF CABLES OR CHAINS ON
PULLING EQUIPMENT DURING FRAME STRAIGHT-
ENING OPERATIONS, PERSONAL INJURY CAN
RESULT.
²DO NOT VENTURE UNDER A HOISTED VEHI-
CLE THAT IS NOT SUPPORTED ON SAFETY
STANDS, PERSONAL INJURY CAN RESULT.
CAUTION: Do not reuse damaged fasteners, quality
of repair would be suspect. Failure to use only pro-
duction fasteners or fasteners of equivalent hard-
ness can result in loosening or failure. Do not drill
holes in top or bottom frame rail flanges, frame rail
failure can result. When using heat to straighten
frame components do not exceed 566ÉC (1050ÉF),
metal fatigue can result.
CAUTION: This procedure is designed to replace
the H-section/spare tire support located at the rear
of the frame assembly. Prior to any cutting, the
vehicle must be mounted on the appropriate frame
repair equipment (ªframe rackº), checked with three
dimensional measuring equipment, and the neces-
sary pull corrections made. If damage remains in
the frame beyond the area covered by this service
part after the pull, the frame must be replaced in its
entirety.
(1) Disconnect and isolate the battery negative
cable.
(2) Remove the cargo box. (Refer to 23 - BODY/EX-
TERIOR/CARGO BOX - REMOVAL)(3) Remove the trailer hitch. (Refer to 13 - FRAME
& BUMPERS/FRAME/TRAILER HITCH -
REMOVAL)
(4) Raise and support the frame so the tires are off
floor.
(5) Remove the shock absorbers. (Refer to 2 - SUS-
PENSION/REAR/SHOCK - REMOVAL)
(6) Remove the rear leaf spring shackle bolts and
let the axle rest on the ground. (Fig. 21)
(7) Remove the spare wheel.
(8) Remove the clip and remove the spare tire
winch tube. (Fig. 22)
Fig. 21 REAR SPRING
1 - SPRING SHACKLE
2 - LEAF SPRING EYE BOLT/NUT
3 - REAR LEAF SPRING
Fig. 22 SPARE TIRE WINCH TUBE
1 - SPARE TIRE WINCH ASSEMBLY
2 - HAIR PIN CLIP
3 - WINCH TUBE
4 - H-SECTION/SPARE WHEEL SUPPORT
DRFRAMES & BUMPERS 13 - 15
FRAME (Continued)

OPERATION
Fuel is returned through the fuel pump module
and back into the fuel tank through the fuel filter/
fuel pressure regulator. A separate fuel return line
from the engine to the tank is not used.
The fuel tank assembly consists of: the fuel tank,
fuel pump module assembly, fuel pump module lock-
nut/gasket, and fuel tank check valve (refer to Fuel
Tank Check Valve for information).
A fuel filler/vent tube assembly using a pressure/
vacuum, 1/4 turn fuel filler cap is used. The fuel
filler tube contains a flap door located below the fuel
fill 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 Emission Control
Systems.
Both fuel filters (at bottom of fuel pump module
and within fuel pressure regulator) are designed for
extended service. They do not require normal sched-
uled maintenance. Filters should only be replaced if
a diagnostic procedure indicates to do so.
STANDARD PROCEDURE - FUEL SYSTEM
PRESSURE RELEASE
Use following procedure if the fuel injector
rail is, or is not equipped with a fuel pressure
test port.
(1) Remove fuel fill cap.
Fig. 1 FUEL DELIVERY COMPONENTS
1 - FUEL TANK 8 - LDP FRESH AIR FILTER
2 - CHECK VALVE 9 - LEAK DETECTION PUMP
3 - LIQUID EXPANSION CHAMBER 10 - EVAP CANISTERS (2)
4 - FUEL FILTER / FUEL PRESSURE REGULATOR 11 - FUEL TANK STRAPS (2)
5 - QUICK-CONNECT FITTING AND FUEL LINE (TO ENGINE) 12 - CHECK VALVE
6 - EVAP LINE CONNECTION 13 - FUEL PUMP MODULE LOCK RING
7 - LEAK DETECTION PUMP FRESH AIR LINE 14 - FUEL PUMP MODULE
14 - 2 FUEL DELIVERY - GASDR
FUEL DELIVERY - GAS (Continued)

FUEL FILTER/PRESSURE
REGULATOR
DESCRIPTION
A combination fuel filter and fuel pressure regula-
tor (Fig. 2) is used on all engines. It is located on the
top of the fuel pump module. A separate frame
mounted fuel filter is not used with any engine.
Both fuel filters (at bottom of fuel pump module
and within fuel pressure regulator) are designed for
extended service. They do not require normal sched-
uled maintenance. Filters should only be replaced if
a diagnostic procedure indicates to do so.
OPERATION
Fuel Pressure Regulator Operation:The pres-
sure regulator is a mechanical device that is not con-
trolled by engine vacuum or the Powertrain Control
Module (PCM).
The regulator is calibrated to maintain fuel system
operating pressure of approximately 339 kPa   34
kPa (49.2 psi   5 psi) at the fuel injectors. It contains
a diaphragm, calibrated springs and a fuel return
valve. The internal fuel filter (Fig. 2) is also part of
the assembly.
Fuel is supplied to the filter/regulator by the elec-
tric fuel pump through an opening tube at the bot-
tom of filter/regulator (Fig. 2).
The regulator acts as a check valve to maintain
some fuel pressure when the engine is not operating.
This will help to start the engine. A second check
valve is located at the outlet end of the electric fuel
ADAPTERS, FUEL PRESSURE TEST, 8.0L - #6539
AND/OR #6631
SPANNER WRENCH - #6856
FITTING, AIR METERING - #6714
O2S (OXYGEN SENSOR) REMOVER/INSTALLER -
#C-4907
Fig. 2 SIDE VIEW - FILTER/REGULATOR
1 - INTERNAL FUEL FILTER
2 - FUEL FLOW TO FUEL INJECTORS
3 - FUEL FILTER/FUEL PRESSURE REGULATOR
4 - EXCESS FUEL BACK TO TANK
5 - FUEL INLET
6 - RUBBER GROMMET
7 - TOP OF PUMP MODULE
14 - 6 FUEL DELIVERY - GASDR
FUEL DELIVERY - GAS (Continued)

pump.Refer to Fuel Pump - Description and
Operation for more information.
If fuel pressure at the pressure regulator exceeds
approximately 49.2 psi, an internal diaphragm opens
and excess fuel pressure is routed back into the tank
through the bottom of pressure regulator.
Both fuel filters (at bottom of fuel pump module
and within fuel pressure regulator) are designed for
extended service. They do not require normal sched-
uled maintenance. Filters should only be replaced if
a diagnostic procedure indicates to do so.
FUEL LEVEL SENDING UNIT /
SENSOR
DESCRIPTION
The fuel gauge sending unit (fuel level sensor) is
attached to the side of the fuel pump module. The
sending unit consists of a float, an arm, and a vari-
able resistor track (card).
OPERATION
The fuel pump module has 4 different circuits
(wires). Two of these circuits are used for the fuel
gauge sending unit for fuel gauge operation, and for
certain OBD II emission requirements. The other 2
wires are used for electric fuel pump operation.
For Fuel Gauge Operation:A constant current
source is supplied to the resistor track on the fuel
gauge sending unit. This is fed directly from the
Powertrain Control Module (PCM).NOTE: For
diagnostic purposes, this 12V power source can
only be verified with the circuit opened (fuel
pump module electrical connector unplugged).
With the connectors plugged, output voltages
will vary from about 0.6 volts at FULL, to about
8.6 volts at EMPTY (about 8.6 volts at EMPTY
for Jeep models, and about 7.0 volts at EMPTY
for Dodge Truck models).The resistor track is
used to vary the voltage (resistance) depending on
fuel tank float level. As fuel level increases, the float
and arm move up, which decreases voltage. As fuel
level decreases, the float and arm move down, which
increases voltage. The varied voltage signal is
returned back to the PCM through the sensor return
circuit.
Both of the electrical circuits between the fuel
gauge sending unit and the PCM are hard-wired (not
multi-plexed). After the voltage signal is sent from
the resistor track, and back to the PCM, the PCM
will interpret the resistance (voltage) data and send
a message across the multi-plex bus circuits to the
instrument panel cluster. Here it is translated into
the appropriate fuel gauge level reading. Refer to
Instrument Panel for additional information.For OBD II Emission Monitor Requirements:
The PCM will monitor the voltage output sent from
the resistor track on the sending unit to indicate fuel
level. The purpose of this feature is to prevent the
OBD II system from recording/setting false misfire
and fuel system monitor diagnostic trouble codes.
The feature is activated if the fuel level in the tank
is less than approximately 15 percent of its rated
capacity. If equipped with a Leak Detection Pump
(EVAP system monitor), this feature will also be acti-
vated if the fuel level in the tank is more than
approximately 85 percent of its rated capacity.
REMOVAL
The fuel level sending unit (fuel level sensor) and
float assembly is located on the side of the fuel pump
module (Fig. 3).
(1) Remove fuel pump module from fuel tank.
Refer to Fuel Pump Module Removal/Installation.
(2) To remove sending unit from pump module, lift
on plastic locking tab (Fig. 4) while sliding sending
unit tracks.
(3) Disconnect 4±wire electrical connector (Fig. 3)
from fuel pump module. Separate necessary sending
unit wiring from connector using terminal pick /
removal tool. Refer to Special Tools in 8W Wiring for
tool part numbers.
Fig. 3 LOCATION - FUEL GAUGE SENDING UNIT
1 - FUEL FILTER / FUEL PRESSURE REGULATOR
2 - FUEL PUMP MODULE ASSEMBLY
3 - 4-WAY ELEC. CONNECT.
4 - FLOAT ARM
5 - ELEC. FUEL PUMP
6 - INLET FILTER
7 - FUEL GAUGE SENDING UNIT
8 - GASKET (SEAL)
DRFUEL DELIVERY - GAS 14 - 7
FUEL FILTER/PRESSURE REGULATOR (Continued)

INSTALLATION
(1) Connect necessary wiring into electrical con-
nectors. Connect 4±wire electrical connector to pump
module.
(2) Position sending unit to pump module. Slide
and snap into place.
(3) Install fuel pump module. Refer to Fuel Pump
Module Removal/Installation.
FUEL LINES
DESCRIPTION
Also refer to Quick-Connect Fittings.
WARNING: THE FUEL SYSTEM MAY BE UNDER A
CONSTANT PRESSURE (EVEN WITH THE ENGINE
OFF). BEFORE SERVICING ANY FUEL SYSTEM
HOSES, FITTINGS, LINES, OR MOST COMPO-
NENTS, FUEL SYSTEM PRESSURE MUST BE
RELEASED. REFER TO THE FUEL SYSTEM PRES-
SURE RELEASE PROCEDURE.
The lines/tubes/hoses used on fuel injected vehicles
are of a special construction. This is due to the
higher fuel pressures and the possibility of contami-
nated fuel in this system. If it is necessary to replace
these lines/tubes/hoses, only those marked EFM/EFI
may be used.
If equipped:The hose clamps used to secure rub-
ber hoses on fuel injected vehicles are of a special
rolled edge construction. This construction is used toprevent the edge of the clamp from cutting into the
hose. Only these rolled edge type clamps may be
used in this system. All other types of clamps may
cut into the hoses and cause high-pressure fuel leaks.
Use new original equipment type hose clamps.
QUICK CONNECT FITTING
DESCRIPTION
Different types of quick-connect fittings are used to
attach various fuel system components, lines and
tubes. These are: a single-tab type, a two-tab type or
a plastic retainer ring type. Some are equipped with
safety latch clips. Some may require the use of a spe-
cial tool for disconnection and removal. Refer to
Quick-Connect Fittings Removal/Installation for more
information.
CAUTION: The interior components (o-rings, clips)
of quick-connect fittings are not serviced sepa-
rately, but new plastic spacers are available for
some types. If service parts are not available, do
not attempt to repair the damaged fitting or fuel line
(tube). If repair is necessary, replace the complete
fuel line (tube) assembly.
STANDARD PROCEDURE - QUICK-CONNECT
FITTINGS
Also refer to Fuel Tubes/Lines/Hoses and Clamps.
Different types of quick-connect fittings are used to
attach various fuel system components, lines and
tubes. These are: a single-tab type, a two-tab type or
a plastic retainer ring type. Safety latch clips are
used on certain components/lines. Certain fittings
may require use of a special tool for disconnection.
DISCONNECTING
WARNING: THE FUEL SYSTEM IS UNDER A CON-
STANT PRESSURE (EVEN WITH ENGINE OFF).
BEFORE SERVICING ANY FUEL SYSTEM HOSE,
FITTING OR LINE, FUEL SYSTEM PRESSURE MUST
BE RELEASED. REFER TO FUEL SYSTEM PRES-
SURE RELEASE PROCEDURE.
CAUTION: The interior components (o-rings, spac-
ers) of some types of quick-connect fitting are not
serviced separately. If service parts are not avail-
able, do not attempt to repair a damaged fitting or
fuel line. If repair is necessary, replace complete
fuel line assembly.
(1) Perform fuel pressure release procedure. Refer
to Fuel Pressure Release Procedure.
Fig. 4 FUEL GAUGE SENDING UNIT - R/I
1 - SENDING UNIT
2 - LOCK TAB
3 - TRACKS
4 - NOTCH
14 - 8 FUEL DELIVERY - GASDR
FUEL LEVEL SENDING UNIT / SENSOR (Continued)

(2) Disconnect negative battery cable from battery.
(3) Clean fitting of any foreign material before dis-
assembly.
(4)2±Button Type Fitting:This type of fitting is
equipped with a push-button located on each side of
quick-connect fitting (Fig. 5). Press on both buttons
simultaneously for removal. Special tools are not
required for disconnection.
(5)Pinch-Type Fitting:This fitting is equipped
with two finger tabs. Pinch both tabs together while
removing fitting (Fig. 6). Special tools are not
required for disconnection.
(6)Single-Tab Type Fitting:This type of fitting
is equipped with a single pull tab (Fig. 7). The tab is
removable. After tab is removed, quick-connect fitting
can be separated from fuel system component. Spe-
cial tools are not required for disconnection.
(a) Press release tab on side of fitting to release
pull tab (Fig. 8).If release tab is not pressed
prior to releasing pull tab, pull tab will be
damaged.
(b) While pressing release tab on side of fitting,
use screwdriver to pry up pull tab (Fig. 8).
(c) Raise pull tab until it separates from quick-
connect fitting (Fig. 9).
(7)Two-Tab Type Fitting:This type of fitting is
equipped with tabs located on both sides of fitting
(Fig. 10). The tabs are supplied for disconnecting
quick-connect fitting from component being serviced.
(a) To disconnect quick-connect fitting, squeeze
plastic retainer tabs (Fig. 10) against sides of
quick-connect fitting with your fingers. Tool use isnot required for removal and may damage plastic
retainer.
(b) Pull fitting from fuel system component
being serviced.
(c) The plastic retainer will remain on compo-
nent being serviced after fitting is disconnected.
The o-rings and spacer will remain in quick-con-
nect fitting connector body.
Fig. 5 2-BUTTON TYPE FITTING
1 - QUICK-CONNECT FITTING
2 - PUSH-BUTTONS (2)
Fig. 6 PINCH TYPE QUICK-CONNECT FITTING
1 - QUICK-CONNECT FITTINGS
2 - PINCH TABS
Fig. 7 SINGLE-TAB TYPE FITTING
1 - PULL TAB
2 - QUICK-CONNECT FITTING
3 - PRESS HERE TO REMOVE PULL TAB
4 - INSERTED TUBE END
DRFUEL DELIVERY - GAS 14 - 9
QUICK CONNECT FITTING (Continued)

(8)Plastic Retainer Ring Type Fitting:This
type of fitting can be identified by the use of a full-
round plastic retainer ring (Fig. 11) usually black in
color.
(a) To release fuel system component from quick-
connect fitting, firmly push fitting towards compo-
nent being serviced while firmly pushing plastic
retainer ring into fitting (Fig. 11). With plastic ring
depressed, pull fitting from component.The plas-
tic retainer ring must be pressed squarely
into fitting body. If this retainer is cocked
during removal, it may be difficult to discon-
nect fitting. Use an open-end wrench on
shoulder of plastic retainer ring to aid in dis-
connection.(b) After disconnection, plastic retainer ring will
remain with quick-connect fitting connector body.
(c) Inspect fitting connector body, plastic retainer
ring and fuel system component for damage.
Replace as necessary.
(9)Latch Clips:Depending on vehicle model and
engine, 2 different types of safety latch clips are used
Fig. 8 DISCONNECTING SINGLE-TAB TYPE FITTING
1 - PULL TAB
2 - SCREWDRIVER
3 - QUICK-CONNECT FITTING
Fig. 9 REMOVING PULL TAB
1 - FUEL TUBE OR FUEL SYSTEM COMPONENT
2 - PULL TAB
3 - QUICK-CONNECT FITTING
4 - FUEL TUBE STOP
Fig. 10 TYPICAL 2±TAB TYPE FITTING
1 - TAB(S)
2 - QUICK-CONNECT FITTING
Fig. 11 PLASTIC RETAINER RING TYPE FITTING
1 - FUEL TUBE
2 - QUICK CONNECT FITTING
3 - PUSH
4 - PLASTIC RETAINER
5 - PUSH
6 - PUSH
7 - PUSH
8 - PUSH
14 - 10 FUEL DELIVERY - GASDR
QUICK CONNECT FITTING (Continued)