1998 DODGE RAM 1500 ECU

FRONT AND REAR CASES
Inspect the cases for wear and damage.
Check case condition. If leaks were a problem, look
for gouges and severe scoring of case sealing sur-
faces. Also make sure the front case mounting studs
are in good condition.
Check the front case mounting studs and vent
tube. The tube can be secured with LoctiteŸ 271 or
680 if loose. The stud threads can be cleaned up with
a die if necessary. Also check condition of the fill/
drain plug threads in the rear case. The threads can
be repaired with a thread chaser or tap if necessary.
Or the threads can be repaired with Helicoiltstain-
less steel inserts if required.
OIL PUMP/OIL PICKUP
Examine the oil pump pickup parts. Replace the
pump if any part appears to be worn or damaged. Do
not disassemble the pump as individual parts are not
available. The pump is only available as a complete
assembly. The pickup screen, hose, and tube are the
only serviceable parts and are available separately.
ASSEMBLY
BEARINGS AND SEALS
(1) Remove the input shaft bearing (Fig. 42) from
the front case with suitable snap-ring pliers.
(2) Transfer the retaining ring to the new bearing
if necessary and install the bearing into the front
case.
(3) Remove the front output shaft bearing retain-
ing ring from inside the front case half.
(4) Using Installer 6436 and Handle C-4171,
remove front output shaft bearing.(5) Start front output shaft bearing in case. Then
seat bearing with Handle C-4171 and Installer 6953
(Fig. 43).
(6) Install front output shaft bearing retaining
ring.
(7) Remove the front output shaft rear bearing
with the screw and jaws from Remover L-4454 and
Cup 8148 (Fig. 44).
Fig. 42 Remove Input Gear Bearing
1 - INPUT GEAR BEARING
2 - FRONT CASE
Fig. 43 Install Front Output Shaft Bearing
1 - FRONT CASE
2 - INSTALLER 6953
3 - HANDLE C-4171
Fig. 44 Front Output Shaft Rear Bearing Removal
1 - REAR CASE
2 - SPECIAL TOOL L-4454-1 AND L-4454-3
3 - SPECIAL TOOL 8148
DRTRANSFER CASE - NV244 GENII 21 - 525
TRANSFER CASE - NV244 GENII (Continued)

SEAL BOOT AND SHIFT MOTOR ASSEMBLY
(1) Install a new seal boot clamp onto the seal
boot.
(2) Install the seal boot (Fig. 76) and clamp onto
the slinger hub and tighten the clamp with Crimp
Tool C-4975-A.
(3) Position the shift motor and mode sensor
assembly onto the transfer case.
(4) Install the bolts (Fig. 77) to hold the shift
motor and mode sensor assembly to the transfer
case. Tighten the bolts to 16-25 N´m (12-18 ft. lbs.).
REAR EXTENSION
(1) Install new seal in rear extension housing seal
with Installer D-163 and Handle C-4171. Verify that
the weep hole in the rubber is oriented downward.
(2) Apply bead of MopartGasket Maker, or equiv-
alent, to mating surface of rear extension housing.
Keep sealer bead width to maximum of 3/16 inch. Do
not use excessive amount of sealer as excess could be
displaced into output bearing.
(3) Align and install rear extension on retainer
(Fig. 78).
(4) Apply MopartSilicone Sealer to threads of rear
extension housing bolts. Then install and tighten
bolts to 16-24 N´m (12-18 ft. lbs.) torque.
INSTALLATION
(1) Mount transfer case on a transmission jack.
(2) Secure transfer case to jack with chains.
(3) Position transfer case under vehicle.
(4) Align transfer case and transmission shafts
and install transfer case onto the transmission.
(5) Install and tighten transfer case attaching nuts
to 27-34 N´m (20-25 ft. lbs.) torque.
(6) Connect the vent hose.
(7) Connect the shift motor and mode sensor wir-
ing connectors. Secure wire harness to clips on trans-
fer case.
(8) Align and connect the propeller shafts.
(9) Fill transfer case with correct fluid. (Refer to
21 - TRANSMISSION/TRANSFER CASE/FLUID -
STANDARD PROCEDURE)
(10) Install skid plate, if equipped.
(11) Remove transmission jack and support stand.
(12) Lower vehicle and verify transfer case shift
operation.
Fig. 76 Install Seal Boot
1 - SEAL BOOT
2 - SEAL SLINGER
Fig. 77 Install the Shift Motor and Mode Sensor
Assembly Bolts - Typical
1 - TRANSFER CASE
2 - SHIFT MOTOR AND MODE SENSOR ASSEMBLY
3 - BOLT
Fig. 78 Install Rear Extension Bolts
1 - EXTENSION HOUSING
2 - TRANSFER CASE
21 - 534 TRANSFER CASE - NV244 GENIIDR
TRANSFER CASE - NV244 GENII (Continued)

Condition Possible Cause Correction
Transfer case noisy while in, or
jumps out of, 4LO mode.1) Transfer case not completely
engaged in 4LO position.1) While rolling 2-3 MPH and the
transmission in NEUTRAL, or clutch
depressed on vehicles equipped
with a manual transmission, shift
transfer case to the 2WD or 4HI
position, and then back into the 4LO
position.
2) Range fork damaged, inserts
worn, or fork is binding on the shift
rail.2) Repair or replace components as
necessary.
3) Low range gear worn or
damaged.3) Repair or replace components as
necessary.
Lubricant leaking from transfer case
seals or vent.1) Transfer case overfilled. 1) Drain lubricant to the correct
level.
2) Transfer case vent closed or
restricted.2) Clean or replace vent as
necessary.
3) Transfer case seals damaged or
installed incorrectly.3) Replace suspect seal.
Abnormal tire wear. 1) Extended operation in 4HI mode
on dry surfaces,1) Operate vehicle in 2WD mode on
dry surfaces.
REMOVAL
(1) Shift transfer case into 2WD.
(2) Raise vehicle.
(3) Drain transfer case lubricant.
(4) Mark front and rear propeller shafts for align-
ment reference.
(5) Support transmission with jack stand.
(6) Remove the transfer case skid plate, if
equipped.
(7) Disconnect front and rear propeller shafts at
transfer case.
(8) Disconnect transfer case shift motor and mode
sensor wire connectors.
(9) Disconnect transfer case vent hose.
(10) Support transfer case with transmission jack.
(11) Secure transfer case to jack with chains.
(12) Remove nuts attaching transfer case to trans-
mission (Fig. 2).
(13) Pull transfer case and jack rearward to disen-
gage transfer case.
(14) Remove transfer case from under vehicle.
DISASSEMBLY
Position transfer case in a shallow drain pan.
Remove drain plug and drain any remaining lubri-
cant remaining in case.
Fig. 2 Remove Transfer Case - Typical
1 - TRANSMISSION
2 - TRANSFER CASE
3 - MODE SENSOR CONNECTOR
21 - 544 TRANSFER CASE - NV273DR
TRANSFER CASE - NV273 (Continued)

Check the front case mounting studs and vent
tube. The tube can be secured with LoctiteŸ 271 or
680 if loose. The stud threads can be cleaned up with
a die if necessary. Also check condition of the fill/
drain plug threads in the rear case. The threads can
be repaired with a thread chaser or tap if necessary.
Or the threads can be repaired with Helicoiltstain-
less steel inserts if required.
OIL PUMP/OIL PICKUP
Examine the oil pump pickup parts. Replace the
pump if any part appears to be worn or damaged. Do
not disassemble the pump as individual parts are not
available. The pump is only available as a complete
assembly. The pickup screen, hose, and tube are the
only serviceable parts and are available separately.
ASSEMBLY
BEARINGS AND SEALS
(1) Remove the input shaft bearing snap-ring from
the front case half with suitable snap-ring pliers.
(2) Remove the input shaft bearing from the front
case half with Installer 6953 and Handle C-4171
(Fig. 43).
(3) Install the input shaft bearing into the front
case half with Installer 8151 inverted on Handle
C-4171 (Fig. 44).
(4) Install the input shaft bearing snap-ring into
the front case half with suitable snap-ring pliers.(5) Remove the front output shaft front bearing
snap-ring from the front case half.
(6) Using Installer 6953 and Handle C-4171 (Fig.
45), remove the front output shaft front bearing.
Fig. 45 Remove Front Output Shaft Front Bearing
1 - FRONT CASE HALF
2 - HANDLE C-4171
3 - INSTALLER 6953Fig. 43 Remove Input Gear Bearing
1 - FRONT CASE HALF
2 - HANDLE C-4171
3 - INSTALLER 6953
Fig. 44 Install Input Gear Bearing
1 - FRONT CASE HALF
2 - HANDLE C-4171
3 - INSTALLER 8151 (INVERTED)
21 - 556 TRANSFER CASE - NV273DR
TRANSFER CASE - NV273 (Continued)

(7) Install the front companion flange onto the
front output shaft.
(8) Install two bolts 180É apart into the front out-
put shaft companion flange.
(9) Place holder over the bolts and against the
companion flange (Fig. 88).
(10) Install a new front companion flange nut.
Tighten the companion flange nut to 176-271 N´m
(130-200 ft.lbs.).
INSTALLATION
(1) Mount transfer case on a transmission jack.
(2) Secure transfer case to jack with chains.
(3) Position transfer case under vehicle.
(4) Align transfer case and transmission shafts
and install transfer case onto the transmission.
(5) Install and tighten transfer case attaching nuts
to 27-34 N´m (20-25 ft. lbs.) torque.
(6) Connect the vent hose.
(7) Connect the shift motor and mode sensor wir-
ing connectors. Secure wire harness to clips on trans-
fer case.
(8) Align and connect the propeller shafts.
(9) Fill transfer case with correct fluid. (Refer to
21 - TRANSMISSION/TRANSFER CASE/FLUID -
STANDARD PROCEDURE)
(10) Install skid plate, if equipped.(11) Remove transmission jack and support stand.
(12) Lower vehicle and verify transfer case shift
operation.
SPECIFICATIONS
TRANSFER CASE - NV273
TORQUE SPECIFICATIONS
DESCRIPTION N-m Ft. Lbs. In. Lbs.
Plug, Detent 16-24 12-18 -
Plug, Drain/Fill 20-34 15-25 -
Bolt, Extension Housing 27-34 20-25 -
Bolt, Case Half 27-34 20-25 -
Support, Sector 27-34 20-25 -
Nuts, Mounting 30-41 20-30 -
Bolts, Shift Motor and
Mode Sensor Assembly16-25 12-18 -
Nut, Companion Flange 176-271 130-200 -
Fig. 88 Install Companion Flange Nut
1 - HOLDER 6719
2 - BOLTS
21 - 568 TRANSFER CASE - NV273DR
TRANSFER CASE - NV273 (Continued)

ROAD TESTING WIND NOISE
(1) Drive the vehicle to verify the general location
of the wind noise.
(2) Apply 50 mm (2 in.) masking tape in 150 mm
(6 in.) lengths along weatherstrips, weld seams or
moldings. After each length is applied, drive the vehi-
cle. If noise goes away after a piece of tape is applied,
remove tape, locate, and repair defect.
POSSIBLE CAUSE OF WIND NOISE
²Moldings standing away from body surface can
catch wind and whistle.
²Gaps in sealed areas behind overhanging body
flanges can cause wind-rushing sounds.
²Misaligned movable components.
²Missing or improperly installed plugs in pillars.
²Weld burn through holes.
STANDARD PROCEDURE
STANDARD PROCEDURE - BODY LUBRICATION
All mechanisms and linkages should be lubricated
when necessary. This will maintain ease of operation
and provide protection against rust and excessive
wear. The weatherstrip seals should be lubricated to
prolong their life as well as to improve door sealing.
All applicable exterior and interior vehicle operat-
ing mechanisms should be inspected and cleaned.
Pivot/sliding contact areas on the mechanisms should
then be lubricated.
(1) When necessary, lubricate the operating mech-
anisms with the specified lubricants.
(2) Apply silicone lubricant to a cloth and wipe it
on door seals to avoid over-spray that can soil pas-
senger's clothing.
(3) Before applying lubricant, the component
should be wiped clean. After lubrication, any excess
lubricant should be removed.
(4) The hood latch, latch release mechanism, latch
striker, and safety latch should be lubricated period-
ically.
(5) The door lock cylinders should be lubricated
twice each year (preferably autumn and spring).
²Spray a small amount of lock cylinder lubricant
directly into the lock cylinder.
²Apply a small amount to the key and insert it
into the lock cylinder.
²Rotate it to the locked position and then back to
the unlocked position several times.
²Remove the key. Wipe the lubricant from it with
a clean cloth to avoid soiling of clothing.
STANDARD PROCEDURE - HEAT STAKING
(1) Remove trim panel.(2) Bend or move the trim panel components at
the heat staked joints. Observe the heat staked loca-
tions and/or component seams for looseness.
(3) Heat stake the components.
(a) If the heat staked or component seam loca-
tion is loose, hold the two components tightly
together and using a soldering gun with a flat tip,
melt the material securing the components
together. Do not over heat the affected area, dam-
age to the exterior of the trim panel may occur.
(b) If the heat staked material is broken or miss-
ing, use a hot glue gun to apply new material to
the area to be repaired. The panels that are being
heat staked must be held together while the apply-
ing the glue. Once the new material is in place, it
may be necessary to use a soldering gun to melt
the newly applied material. Do not over heat the
affected area, damage to the exterior of the trim
panel may occur.
(4) Allow the repaired area to cool and verify the
repair.
(5) Install trim panel.
STANDARD PROCEDURE - PLASTIC BODY
PANEL REPAIR
There are many different types of plastics used in
today's automotive environment. We group plastics in
three different categories: Rigid, Semi-Rigid, and
Flexible. Any of these plastics may require the use of
an adhesion promoter for repair. These types of plas-
tic are used extensively on DaimlerChrysler Motors
vehicles. Always follow repair material manufactur-
er's plastic identification and repair procedures.
Rigid Plastics:
Examples of rigid plastic use: Fascias, Hoods,
Doors, and other Body Panels, which include SMC,
ABS, and Polycarbonates.
Semi-Rigid Plastics:
Examples of semi-rigid plastic use: Interior Panels,
Under Hood Panels, and other Body Trim Panels.
Flexible Plastics:
Examples of flexible plastic use: Fascias, Body
Moldings, and upper and lower Fascia Covers.
Repair Procedure:
The repair procedure for all three categories of
plastics is basically the same. The one difference is
the material used for the repair. The materials must
be specific for each substrate, rigid repair material
for rigid plastic repair, semi-rigid repair material for
semi-rigid plastic repair and flexible repair material
for flexible plastic repair.
DRBODY 23 - 3
BODY (Continued)

(7) Drill 3 mm (0.125 in.) holes in the support
squares 13 mm (0.5 in.) from the edge in the center
of one side.
(8) Scuff the backside of the body panel around the
cutout hole with a scuff pad or sandpaper.
(9) Mix enough adhesive to cover one side of all
support squares.
(10) Apply adhesive to cover one side of all support
squares.
(11) Using number 8 sheet metal screws, secure
support squares to back side of body panel with
adhesive sandwiched between the panel and squares
(Fig. 9).
(12) Position patch in cutout against support
squares and adjust patch until the gap is equal along
all sides (Fig. 10).
(13) Drill 3 mm (0.125 in.) holes in the support
squares through the pre-drilled holes in the patch.
(14) Apply a coat of adhesive to the exposed ends
of the support squares (Fig. 11).
(15) Install screws to hold the patch to support
squares (Fig. 12). Tighten screws until patch surface
is flush with panel surface.
(16) Allow adhesive to cure, and remove all screws.
(17) Using a 125 mm (5 in.) 24 grit disc grinder,
grind a 50 mm (2 in.) to 75 mm (3 in.) wide and 2
mm (0.080 in.) deep path across the gaps around the
patch (Fig. 13). With compressed air, blow dust from
around patch.(18) Apply adhesive backed nylon mesh (dry wall
tape) over gaps around patch (Fig. 14).
(19) Mix enough adhesive to cover the entire patch
area.
(20) Apply adhesive over the mesh around patch,
and smooth epoxy with a wide spreader to reduce fin-
ish grinding. Use two to three layers of mesh and
adhesive to create a stronger repair (Fig. 15).
Fig. 9 SECURE SUPPORT SQUARES TO BODY
PANEL
1 - SUPPORT SQUARES
2 - SCREWS
3 - DAMAGED BODY PANEL
Fig. 10 POSITION PATCH IN CUTOUT AND ALIGN
1 - CUTOUT
2 - SUPPORT SQUARES
Fig. 11 APPLY ADHESIVE TO SUPPORT SQUARES
1 - APPLICATOR
2 - SUPPORT SQUARES
3 - ADHESIVE
DRBODY 23 - 9
BODY (Continued)

TAILGATE
TABLE OF CONTENTS
page page
CHECK CABLE
REMOVAL.............................15
INSTALLATION.........................15
COVER
REMOVAL.............................16
INSTALLATION.........................16
HINGE
REMOVAL.............................16
INSTALLATION.........................16
LATCH
REMOVAL.............................16INSTALLATION.........................16
LATCH STRIKER
REMOVAL.............................16
INSTALLATION.........................17
RELEASE HANDLE/LATCH REMOTE
REMOVAL.............................17
INSTALLATION.........................17
TAILGATE
REMOVAL.............................17
INSTALLATION.........................17
CHECK CABLE
REMOVAL
(1) Open tailgate.
(2) Pry lock tab outward to clear stud head on
cargo box (Fig. 1).
(3) Push cable end forward until stud head is in
clearance hole portion of cable end.
(4) Separate cable end from stud.
(5) Remove screw attaching cable to tailgate. (Fig.
2)
(6) Separate check cable from tailgate.
INSTALLATION
(1) Position check cable on tailgate.
(2) Install bolt attaching small end of cable to tail-
gate.
(3) Tighten tailgate check cable bolt to 23 N´m (17
ft. lbs.).
(4) Position large end of cable onto stud head and
slide downward to secure lock tab.
Fig. 1 Tailgate Check
1 - TAILGATE STRIKER
2 - SCREW DRIVER
3 - TAILGATE CHECK CABLE
4 - LOCK TAB
Fig. 2 LATCH HANDLE - LATCH
1 - EXTERIOR HANDLE
2 - CONTROL ASSEMBLY
3 - NUTS (2)
4 - TAILGATE
5-LATCH
6 - CHECK CABLE
7 - CHECK/LATCH BOLT
8 - LATCH BOLT
DRTAILGATE 23 - 15