1998 DODGE RAM 1500 IPM

(7) Remove the front cab mount bolt to the Front
End Sheet Metal (FESM) bracket. (Fig. 5)
(8) Make a vertical mark on the inside and outside
face of the frame rail 112 mm (4.5 in.) from the for-
ward edge of the PLP hole in the sides of the rail.
(Fig. 7)
(9) Using a straightedge, connect the two lines on
the top and bottom of the rail.
(10) Using the service tip as a guide, re-check your
cut lines to ensure the service tip will fit when the
cut is made.
CAUTION: Do not use any flame or plasma cutting
equipment to cut the frame in this procedure. This
is due to the inaccurate nature of the cut-line and
the fact that the high temperatures achieved duringflame or plasma cutting will change the metal char-
acteristics and may weaken the frame and/or repair
location.
(11) Using a reciprocating saw or equivalent, care-
fully cut and remove the damaged frame rail tip.
(Fig. 6)
(12) Assemble the service sleeve. Refer to SER-
VICE SLEEVE ASSEMBLY at the end of this proce-
dure.
NOTE: Any burned surface coatings will need to be
removed from the sleeve prior to installation and
application of corrosion preventative coatings.
(13) Smooth and square the cut edges of the origi-
nal frame. (Fig. 6)
Fig. 5 REPLACEMENT FRAME TIP
1 - FRONT END SHEET METAL (FESM) BRACKET
2 - CAB INSULATOR
3 - RING-FILLET WELD/HOLE
4 - PRINCIPLE LOCATING POINT (PLP)
5 - WELD ROOT GAP 4 mm-6mm(0.16 in. - 0.24 in.)
6 - FRONT CAB MOUNT BOLT
7 - REPLACEMENT FRAME TIP
Fig. 6 FRAME CUT LOCATION
1 - REPAIR ROOT OPENING
2 - SERVICE SLEEVE
3 - PRINCIPLE LOCATING POINT (PLP)
4 - SUSPENSION BRACKETS
5 - FRAME
6 - FRAME CUTOFF LOCATION - 112 mm (4.5 in.)
7 - FRAME SERVICE TIP
DRFRAMES & BUMPERS 13 - 5
FRAME (Continued)

(20) Apply ring-fillet welds into the ring-fillet weld
holes on the replacement frame tip (Fig. 13). (Refer
to 13 - FRAME & BUMPERS/FRAME - SPECIFICA-
TIONS - WELDING)
(21) Install the upper FESM insulator onto the
replacement tip and position the service sleeve/re-
placement tip into the existing frame rail.
(22) Loosely install the lower FESM insulator and
cab mounting bolt.
(23) Using the appropriate measuring equipment,
verify the front end sheet metal bracket's location in
all three (X,Y, and Z) planes of space, and adjust if
required. (Fig. 14)
CAUTION: Shield the surrounding area and compo-
nents from exposure to the welding spatter and
heat.(24) When correctly fitted and a weld root gap of 4
mm minimum to 6 mm maximum (0.16 in - 0.24 in)
is established, tack the ring fillet welds to hold the
tip in position, then complete the ring fillet welds.
NOTE: Ring-fillet welds may be filled in with weld
material if an improved cosmetic appearance is
desired.
Fig. 11 4X4 TAPPING PLATE/SLEEVE
INSTALLATION
1 - REPLACEMENT FRAME TIP
2 - FRAME RAIL
3 - SERVICE SLEEVE
4 - PLP
5 - SWAY BAR MOUNTING BRACKET
6 - TAPPING PLATE
7 - ROOT WELD GAP
8 - SLEEVE TAB
Fig. 12 4X4 TAPPING PLATE/SLEEVE
INSTALLATION
1 - REPLACEMENT FRAME TIP
2 - ROOT WELD GAP
3 - SERVICE SLEEVE
4 - SWAY BAR MOUNTING BRACKET
5 - TAPPING PLATE
6 - SLEEVE TAB
13 - 8 FRAMES & BUMPERSDR
FRAME (Continued)

STANDARD PROCEDURE - HYDROFORM
FENDER RAIL REPAIR
CAUTION: This repair procedure assumes damage
to the right or left hydroform fender rail (Fig. 18).
Prior to any repairs, the vehicle must be mounted
on the appropriate frame repair equipment (ªframe
rackº), checked with three dimensional measuring
equipment, and necessary pull corrections made. If
damage exists in the hydroform fender rail, or cab
beyond the area covered by this service procedure
after dimensional corrections are made, the hydro-
form must be replaced in its entirety. Refer to 23 -
BODY/BODY STRUCTURE/WELD LOCATIONS -
SPECIFICATIONS, when replacing the entire hydro-
form.
(1) Before proceding with this repair procedure
review the required service warnings and precau-
tions. (Refer to 13 - FRAME & BUMPERS/FRAME -
WARNING)
(2) Disconnect and isolate the battery negative
cable.
(3) Remove the front wheelhouse splash shield.
(Refer to 23 - BODY/EXTERIOR/FRONT WHEEL-
HOUSE SPLASH SHIELD - REMOVAL)(4) Remove the fender. (Refer to 23 - BODY/EXTE-
RIOR/FRONT FENDER - REMOVAL)
(5) Remove the A/C condenser, if required. (Refer
to 24 - HEATING & AIR CONDITIONING/PLUMB-
ING/A/C CONDENSER - REMOVAL)
(6) Remove the A/C lines, if required. Refer to the
Heating and Air Conditioning section of the manual
for recommended procedures.
(7) Remove the radiator assembly. (Refer to 7 -
COOLING/ENGINE/RADIATOR - REMOVAL)
(8) Remove the air cleaner and support bracket, if
required. (Refer to 9 - ENGINE/AIR INTAKE SYS-
TEM/AIR CLEANER ELEMENT - REMOVAL)
(9) Remove the integrated power module. (Refer to
8 - ELECTRICAL/POWER DISTRIBUTION/INTE-
GRATED POWER MODULE - REMOVAL)
(10) Remove the bolts and position aside the wire
harness and grounds, if required.
(11) Remove the upper radiator crossmember.
(Refer to 23 - BODY/EXTERIOR/UPPER RADIATOR
CROSSMEMBER - REMOVAL)
(12) Remove the headlamp unit. (Refer to 8 -
ELECTRICAL/LAMPS/LIGHTING - EXTERIOR/
HEADLAMP UNIT - REMOVAL)
(13) Remove the front cab mount to the Front End
Sheet Metal bracket (FESM) bolt.
Fig. 18 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 - 11
FRAME (Continued)

(14) Remove the bolts attaching the lower radiator
crossmember to the hydroform fender rail. (Fig. 18)
CAUTION: Do not use any flame or plasma cutting
equipment to cut the frame in this procedure. The
inaccurate and high temperatures achieved during
flame or plasma cutting will change the metal char-
acteristics and may weaken the frame and/or repair
location.
(15) Using a reciprocating saw or equivalent, cut
the fender rail and shotgun at a straight and square
section of the hydroform and remove.
(16) Smooth and square the cut edges.
(17) Using the damaged structure as a reference
cut the service part at the same location as the first
cut. Smooth and square the cut edges.
NOTE: The repair structure should butt up to the
remaining structure and provide the same overall
vehicle geometry.
(18) 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.
(19) Remove any paint or e-coat from the inserts
and also to the interior and exterior of the hydro-
forms.
(20) 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.
(21) Install the insert 1º into the replacement part
and tack into place with a weld. (Refer to 13 -
FRAME & BUMPERS/FRAME - SPECIFICATIONS -
WELDING)
(22) Insert the service part into place and using
the appropriate measuring equipment, verify the
front end sheet metal bracket's location in all three
(X,Y, and Z) planes of space. (Fig. 19)
(23) 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 theisolator and hole in the frame perch mount. Also
ensure the lower radiator closure tube is bolted into
the forward shotgun ends.
(24) Complete welding by making a 360É butt weld
around the fender rails.
(25) Metal finish the exposed welds on the hydro-
forms.
(26) 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.
(27) Install the front cab mount bolt if previously
removed and tighten to 81 N´m (60 ft. lbs.).
(28) Install the lower radiator crossmember bolts
and tighten to 28 N´m (21 ft. lbs.).
(29) Install the headlamp unit. (Refer to 8 - ELEC-
TRICAL/LAMPS/LIGHTING - EXTERIOR/HEAD-
LAMP UNIT - INSTALLATION)
(30) Install the upper radiator crossmember. (Refer
to 23 - BODY/EXTERIOR/UPPER RADIATOR
CROSSMEMBER - INSTALLATION)
(31) Install the wire harness and ground if previ-
ously removed and install the bolts.
(32) Install the integrated power module, if previ-
ously removed. (Refer to 8 - ELECTRICAL/POWER
DISTRIBUTION/INTEGRATED POWER MODULE -
INSTALLATION)
(33) Install the air cleaner bracket and air cleaner,
if previously removed. (Refer to 9 - ENGINE/AIR
INTAKE SYSTEM/AIR CLEANER ELEMENT -
INSTALLATION)
(34) Install the radiator assembly. (Refer to 7 -
COOLING/ENGINE/RADIATOR - INSTALLATION)
(35) Install the A/C lines, if previously removed.
Refer to the Heating and Air Conditioning section of
the manual for the recommended procedures.
(36) Install the A/C condenser, if previously
removed. (Refer to 24 - HEATING & AIR CONDI-
TIONING/PLUMBING/A/C CONDENSER - INSTAL-
LATION)
(37) Install the fender. (Refer to 23 - BODY/EXTE-
RIOR/FRONT FENDER - INSTALLATION)
(38) Install the front wheelhouse splash shield.
(Refer to 23 - BODY/EXTERIOR/FRONT WHEEL-
HOUSE SPLASH SHIELD - INSTALLATION)
(39) Reconnect the battery ground.
13 - 12 FRAMES & BUMPERSDR
FRAME (Continued)

STANDARD PROCEDURE - REAR FRAME
H-SECTION REPLACEMENT
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) Before proceding with this repair procedure
review the required service warnings and precau-
tions. (Refer to 13 - FRAME & BUMPERS/FRAME -
WARNING)
(2) Disconnect and isolate the battery negative
cable.
(3) Remove the cargo box. (Refer to 23 - BODY/EX-
TERIOR/CARGO BOX - REMOVAL)
(4) Remove the trailer hitch. (Refer to 13 - FRAME
& BUMPERS/FRAME/TRAILER HITCH -
REMOVAL)
(5) Raise and support the frame so the tires are off
floor.(6) Remove the shock absorbers. (Refer to 2 - SUS-
PENSION/REAR/SHOCK - REMOVAL)
(7) Remove the rear leaf spring shackle bolts and
let the axle rest on the ground. (Fig. 20)
(8) Remove the spare wheel.
Fig. 19 ENGINE COMPARTMENT/FRONT STRUCTURE
Fig. 20 REAR SPRING
1 - SPRING SHACKLE
2 - LEAF SPRING EYE BOLT/NUT
3 - REAR LEAF SPRING
DRFRAMES & BUMPERS 13 - 13
FRAME (Continued)

(9) Remove the clip and remove the spare tire
winch tube. (Fig. 21)
(10) Remove the bolts and remove the spare tire
winch. (Fig. 22)
(11) Position the wire harness forward of the work
area.
CAUTION: Do not use any flame or plasma cutting
equipment to cut the frame in this procedure. The
inaccurate and high temperatures achieved during
flame or plasma cutting will change the metal char-
acteristics and may weaken the frame and/or repair
location.(12) Carefully remove the H-section welds using a
grinder or equivalent tool.
(13) Remove the H-section and clean any remain-
ing welds from the frame.
(14) Trial fit the replacement part.
(15) Remove all e-coat from within 25 mm (1.0 in.)
of the weld area.
(16) Using the appropriate measuring equipment,
position the replacement part and verify correct posi-
tioning in all three (X,Y, and Z) planes of space.
(Refer to 13 - FRAME & BUMPERS/FRAME - SPEC-
IFICATIONS - FRAME DIMENSIONS)
CAUTION: Shield the surrounding area and compo-
nents from exposure to the welding spatter and
heat.
(17) Weld the replacement H-section into position.
The welding should be performed in a skip (stitch)
type method to minimize the heat buildup following
I-CAR or the American Welding Society welding pro-
cedures and utilizing the process specifications at the
end of this section. (Refer to 13 - FRAME &
BUMPERS/FRAME - SPECIFICATIONS - WELD-
ING)
(18) Dress the welded area and apply corrosion
resistant coatings inside and out.
(a) Inside the rail, inject a creeping wax based
rust inhibitor compound through the existing holes
in the frame ensuring 100% coverage including the
mating face between the frame and replacement
H-section.
(b) Apply a durable top coat to the outside of the
repair area.
(19) Position the wiring harness back.
CAUTION: Inspect the tire winch assembly for dam-
age. If any one or more of the following are evident,
replace the winch assembly.
²Indications of cracked or bulging plastic.
²Housing flanges are bent or cracked.
²If winch was loose before repair.
(20) Install the spare tire winch and install the
bolts. (Fig. 22)
(21) Tighten the bolts to 41 N´m (30 ft. lbs.).
(22) Install the spare tire winch tube and install
the clip. (Fig. 21)
(23) Install the spare tire.
CAUTION: Check operation of the spare tire winch
by manipulating it up and down. If the winch binds
or jambs, replace the winch assembly.
(24) Lift the axle into position and install the rear
shackle bolts. (Fig. 20)
(25) Tighten the bolts to 163 N´m (120 ft. lbs.).
Fig. 21 SPARE TIRE WINCH TUBE
1 - SPARE TIRE WINCH ASSEMBLY
2 - HAIR PIN CLIP
3 - WINCH TUBE
4 - H-SECTION/SPARE WHEEL SUPPORT
Fig. 22 SPARE TIRE WINCH ASSEMBLY
1 - SPARE TIRE WINCH ASSEMBLY
2 - BOLTS
3 - RETAINER BRACKET
4 - H-SECTION/SPARE WHEEL SUPPORT
13 - 14 FRAMES & BUMPERSDR
FRAME (Continued)

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.
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 to
prevent 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.
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)
Fig. 4 FUEL GAUGE SENDING UNIT - R/I
1 - SENDING UNIT
2 - LOCK TAB
3 - TRACKS
4 - NOTCH
DRFUEL DELIVERY - GAS 14 - 7
FUEL LEVEL SENDING UNIT / SENSOR (Continued)

REMOVAL
The fuel pump relay is located in the Power Distri-
bution Center (PDC) (Fig. 13). Refer to label on PDC
cover for relay location.
(1) Remove PDC cover.
(2) Remove relay from PDC.
(3) Check condition of relay terminals and PDC
connector terminals for damage or corrosion. Repair
if necessary before installing relay.
(4) Check for pin height (pin height should be the
same for all terminals within the PDC connector).
Repair if necessary before installing relay.
INSTALLATION
The fuel pump relay is located in the Power Distri-
bution Center (PDC). Refer to label on PDC cover for
relay location.
(1) Install relay to PDC.
(2) Install cover to PDC.
IDLE AIR CONTROL MOTOR
DESCRIPTION
A separate IAC motor is not used with the 5.7L V-8
engine.
The IAC stepper motor is mounted to the throttle
body, and regulates the amount of air bypassing the
control of the throttle plate. As engine loads and
ambient temperatures change, engine rpm changes.
A pintle on the IAC stepper motor protrudes into apassage in the throttle body, controlling air flow
through the passage. The IAC is controlled by the
Powertrain Control Module (PCM) to maintain the
target engine idle speed.
OPERATION
A separate IAC motor is not used with the 5.7L V-8
engine.
At idle, engine speed can be increased by retract-
ing the IAC motor pintle and allowing more air to
pass through the port, or it can be decreased by
restricting the passage with the pintle and diminish-
ing the amount of air bypassing the throttle plate.
The IAC is called a stepper motor because it is
moved (rotated) in steps, or increments. Opening the
IAC opens an air passage around the throttle blade
which increases RPM.
The PCM uses the IAC motor to control idle speed
(along with timing) and to reach a desired MAP dur-
ing decel (keep engine from stalling).
The IAC motor has 4 wires with 4 circuits. Two of
the wires are for 12 volts and ground to supply elec-
trical current to the motor windings to operate the
stepper motor in one direction. The other 2 wires are
also for 12 volts and ground to supply electrical cur-
rent to operate the stepper motor in the opposite
direction.
To make the IAC go in the opposite direction, the
PCM just reverses polarity on both windings. If only
1 wire is open, the IAC can only be moved 1 step
(increment) in either direction. To keep the IAC
motor in position when no movement is needed, the
PCM will energize both windings at the same time.
This locks the IAC motor in place.
In the IAC motor system, the PCM will count
every step that the motor is moved. This allows the
PCM to determine the motor pintle position. If the
memory is cleared, the PCM no longer knows the
position of the pintle. So at the first key ON, the
PCM drives the IAC motor closed, regardless of
where it was before. This zeros the counter. From
this point the PCM will back out the IAC motor and
keep track of its position again.
When engine rpm is above idle speed, the IAC is
used for the following:
²Off-idle dashpot (throttle blade will close quickly
but idle speed will not stop quickly)
²Deceleration air flow control
²A/C compressor load control (also opens the pas-
sage slightly before the compressor is engaged so
that the engine rpm does not dip down when the
compressor engages)
²Power steering load control
The PCM can control polarity of the circuit to con-
trol direction of the stepper motor.
Fig. 13 PDC LOCATION
1 - BATTERY
2 - INTEGRATED POWER MODULE (IPM)
14 - 28 FUEL INJECTION - GASDR
FUEL PUMP RELAY (Continued)