1998 DODGE RAM 1500 change time

(11) Install air resonator tube to throttle body.
(12) Before starting engine, operate accelerator
pedal to check for any binding.
5.7L V-8
(1) Attach cable to Accelerator Pedal Position Sen-
sor (APPS). Refer to APPS Removal / Installation.
(2) Push cable housing into rubber grommet and
through opening in dash panel.
(3) From inside vehicle, install clip holding cable
to dashpanel (Fig. 1).
(4) From inside vehicle, slide throttle cable core
wire into opening in top of pedal arm.
(5) Push cable retainer (clip) into pedal arm open-
ing until it snaps in place.
(6) Before starting engine, operate accelerator
pedal to check for any binding.
(7) If necessary, use DRB IIItScan Tool to erase
any APPS Diagnostic Trouble Codes (DTC's) from
PCM.
THROTTLE POSITION SENSOR
DESCRIPTION
The 3-wire Throttle Position Sensor (TPS) is
mounted on the throttle body and is connected to the
throttle blade shaft.
The 5.7L V-8 engine does not use a separate TPS
on the throttle body.
OPERATION
The 5.7L V-8 engine does not use a separate Throt-
tle Position Sensor (TPS) on the throttle body.
The 3±wire TPS provides the Powertrain Control
Module (PCM) with an input signal (voltage) that
represents the throttle blade position of the throttle
body. The sensor is connected to the throttle blade
shaft. As the position of the throttle blade changes,
the output voltage of the TPS changes.
The PCM supplies approximately 5 volts to the
TPS. The TPS output voltage (input signal to the
PCM) represents the throttle blade position. The
PCM receives an input signal voltage from the TPS.
This will vary in an approximate range of from .26
volts at minimum throttle opening (idle), to 4.49 volts
at wide open throttle. Along with inputs from other
sensors, the PCM uses the TPS input to determine
current engine operating conditions. In response to
engine operating conditions, the PCM will adjust fuel
injector pulse width and ignition timing.The PCM needs to identify the actions and position
of the throttle blade at all times. This information is
needed to assist in performing the following calcula-
tions:
²Ignition timing advance
²Fuel injection pulse-width
²Idle (learned value or minimum TPS)
²Off-idle (0.06 volt)
²Wide Open Throttle (WOT) open loop (2.608
volts above learned idle voltage)
²Deceleration fuel lean out
²Fuel cutoff during cranking at WOT (2.608 volts
above learned idle voltage)
²A/C WOT cutoff (certain automatic transmis-
sions only)
REMOVAL
3.7L V6
The Throttle Position Sensor (TPS) is mounted to
the throttle body (Fig. 37), or (Fig. 38).
(1) Remove air resonator tube at throttle body.
(2) Disconnect TPS electrical connector.
(3) Remove 2 TPS mounting screws.
(4) Remove TPS.
Fig. 37 TPS LOCATION - 3.7L V-6
1 - THROTTLE POSITION SENSOR (TPS)
2 - MOUNTING SCREWS
3 - IDLE AIR CONTROL MOTOR (IAC)
4 - MOUNTING SCREWS
DRFUEL INJECTION - GAS 14 - 41
THROTTLE CONTROL CABLE (Continued)

INSTALLATION
Engine Mounted Sensor :
The APPS is serviced (replaced) as one assembly
including the lever, brackets and sensor. The APPS is
calibrated to its mounting bracket.
(1) Snap electrical connector into bottom of sensor.
(2) Position APPS assembly to engine and install 6
bolts. Tighten bolts to 24 N´m (18 ft. lbs.) torque.
(3) Connect wiring harness clip at bottom of
bracket.
(4) Refer to Group 21, Transmission for transmis-
sion control cable installation procedures.
(5) Install speed control cable into mounting
bracket. Be sure pinch tabs have secured cable.
(6) Install throttle cable into mounting bracket. Be
sure pinch tabs have secured cable.
(7) Connect throttle cable at lever (snaps on).
(8) Connect speed control cable to lever by pushing
cable connector rearward onto lever pin while hold-
ing lever forward.
(9) Install cable cover.
(10) Connect both negative battery cables to both
batteries.
(11) If necessary, use DRB IIItScan Tool to erase
any Diagnostic Trouble Codes (DTC's) from ECM.Battery Tray Mounted Sensor :
(1) Install Accelerator Pedal Position Sensor
(APPS) cable to accelerator pedal. Refer to Accelera-
tor Pedal Removal / Installation.
(2) Connect electrical connector to APPS.
(3) If necessary, connect cable to APPS lever ball
socket (snaps on).
(4) Snap APPS cable cover closed.
(5) Position APPS assembly to bottom of battery
tray and install 3 bolts. Refer to Torque Specifica-
tions.
(6) Install wheelhouse liner. Refer to Body.
(7) Perform the following procedure:
(a) Connect negative battery cables to both bat-
teries.
(b) Turn key switch ON, but do not crank
engine.
(c) Leave key switch ON for a minimum of 10
seconds. This will allow ECM to learn electrical
parameters.
(8) If necessary, use DRB IIItScan Tool to erase
any Diagnostic Trouble Codes (DTC's) from ECM.
CAMSHAFT POSITION
SENSOR
DESCRIPTION
The Camshaft Position Sensor (CMP) on the 5.9L
diesel engine is located below the fuel injection
pump. It is bolted to the back of the timing gear
housing.
OPERATION
The diesel Camshaft Position Sensor (CMP) con-
tains a hall effect device. A rotating target wheel
(tonewheel) for the CMP is located on the camshaft
gear. This hall effect device detects notches located
on the back side of the camshaft gear. As the cam-
shaft gear rotates, the notches pass the tip of the
CMP.
When the leading edge of the notch passes the tip
of the CMP, the following occurs: The interruption of
magnetic field causes the voltage to switch high
resulting in a signal of approximately 5 volts.
When the trailing edge of the notch passes the tip
of the CMP, the following occurs: The change of the
magnetic field causes the signal voltage to switch low
to 0 volts.
The CMP (Fig. 8) provides a signal to the Engine
Control Module (ECM) at all times when the engine
is running. The ECM uses the CMP information pri-
marily on engine start-up. Once the engine is run-
ning, the ECM uses the CMP as a backup sensor for
engine speed. The Crankshaft Position Sensor (CKP)
Fig. 7 APPS CABLE (OFF ENGINE MOUNTING)
1 - APPS LEVER
2 - BALL SOCKET
3 - SWING-DOWN DOOR
4 - CABLE CLIP
5 - CABLE
DRFUEL INJECTION - DIESEL 14 - 71
ACCELERATOR PEDAL POSITION SENSOR (Continued)

When the leading edge of the tonewheel notch
passes the tip of the CKP, the following occurs: The
interruption of magnetic field causes the voltage to
switch high resulting in a signal of approximately 5
volts.
When the trailing edge of the tonewheel notch
passes the tip of the CKP, the following occurs: The
change of the magnetic field causes the signal voltage
to switch low to 0 volts.
The Camshaft Position Sensor (CMP) also provides
a signal to the Engine Control Module (ECM) at all
times when the engine is running. The ECM uses
this CMP information primarily on engine start-up.
Once the engine is running, the ECM uses the CMP
as a backup sensor for engine speed.
REMOVAL
(1) Raise and support vehicle
(2) Disconnect electrical connector at CKP sensor
(Fig. 12).
(3) Remove 1 sensor mounting bolt.
(4) Remove CKP sensor.
INSTALLATION
(1) Position and install CKP sensor to engine.
(2) Install 1 sensor mounting bolt and tighten to 9
N´m (80 in. lbs.) torque.(3) Install electrical connector to CKP sensor (Fig.
12).
Fig. 10 5.9L DIESEL CKP
1 - ENGINE HARMONIC BALANCER
2 - FRONT OF TIMING GEAR COVER
3 - CKP MOUNTING BOLT
4 - ELEC. CONNECTOR
5 - CKP SENSOR
6 - NOTCHES
Fig. 11 CKP NOTCHED TONEWHEEL
1 - ENGINE HARMONIC BALANCER
2 - NOTCHED TONEWHEEL
3 - FRONT OF CRANKSHAFT
Fig. 12 5.9L DIESEL CKP
1 - ENGINE HARMONIC BALANCER
2 - FRONT OF TIMING GEAR COVER
3 - CKP MOUNTING BOLT
4 - ELEC. CONNECTOR
5 - CKP SENSOR
6 - NOTCHES
DRFUEL INJECTION - DIESEL 14 - 73
CRANKSHAFT POSITION SENSOR (Continued)

sure curve is higher than normal to make the
transmission shift at normal speeds and sooner. The
PCM uses a temperature sensor in the transmission
oil sump to determine when low temperature gover-
nor pressure is needed.
NORMAL OPERATION
Normal operation is refined through the increased
computing power of the PCM and through access to
data on engine operating conditions provided by the
PCM that were not available with the previous
stand-alone electronic module. This facilitated the
development of a load adaptive shift strategy - the
ability to alter the shift schedule in response to vehi-
cle load condition. One manifestation of this capabil-
ity is grade9hunting9prevention - the ability of the
transmission logic to delay an upshift on a grade if
the engine does not have sufficient power to main-
tain speed in the higher gear. The 3-2 downshift and
the potential for hunting between gears occurs with a
heavily loaded vehicle or on steep grades. When
hunting occurs, it is very objectionable because shifts
are frequent and accompanied by large changes in
noise and acceleration.
WIDE OPEN THROTTLE OPERATION
In wide-open throttle (WOT) mode, adaptive mem-
ory in the PCM assures that up-shifts occur at the
preprogrammed optimum speed. WOT operation is
determined from the throttle position sensor, which
is also a part of the emission control system. The ini-
tial setting for the WOT upshift is below the opti-
mum engine speed. As WOT shifts are repeated, the
PCM learns the time required to complete the shifts
by comparing the engine speed when the shifts occur
to the optimum speed. After each shift, the PCM
adjusts the shift point until the optimum speed is
reached. The PCM also considers vehicle loading,
grade and engine performance changes due to high
altitude in determining when to make WOT shifts. It
does this by measuring vehicle and engine accelera-
tion and then factoring in the shift time.
TRANSFER CASE LOW RANGE OPERATION
On four-wheel drive vehicles operating in low
range, the engine can accelerate to its peak more
rapidly than in Normal range, resulting in delayed
shifts and undesirable engine9flare.9The low range
governor pressure curve is also higher than normal
to initiate upshifts sooner. The PCM compares elec-
tronic vehicle speed signal used by the speedometer
to the transmission output shaft speed signal to
determine when the transfer case is in low range.REMOVAL
(1) Hoist and support vehicle on safety stands.
(2) Remove transmission fluid pan and filter.
(3) Disengage wire connectors from pressure sen-
sor and solenoid (Fig. 78).
(4) Remove screws holding pressure solenoid
retainer to governor body.
(5) Separate solenoid retainer from governor (Fig.
79).
Fig. 78 Governor Solenoid And Pressure Sensor
1 - PRESSURE SENSOR
2 - PRESSURE SOLENOID
3 - GOVERNOR
Fig. 79 Pressure Solenoid Retainer
1 - PRESSURE SOLENOID RETAINER
2 - GOVERNOR
DRAUTOMATIC TRANSMISSION - 48RE 21 - 199
ELECTRONIC GOVERNOR (Continued)

TRANSFER CASE - NV243
TABLE OF CONTENTS
page page
TRANSFER CASE - NV243
DESCRIPTION........................482
OPERATION..........................483
DIAGNOSIS AND TESTING - TRANSFER
CASE - NV243.......................483
REMOVAL............................484
DISASSEMBLY........................484
CLEANING...........................493
INSPECTION.........................493
ASSEMBLY...........................496
INSTALLATION........................505
SPECIFICATIONS
TRANSFER CASE - NV243.............505
SPECIAL TOOLS
TRANSFER CASE - NV243.............506
EXTENSION HOUSING SEAL
REMOVAL............................507
INSTALLATION........................507FLUID
STANDARD PROCEDURE - FLUID DRAIN AND
REFILL............................507
FRONT OUTPUT SHAFT SEAL
REMOVAL............................507
INSTALLATION........................508
MODE SENSOR
DESCRIPTION........................509
OPERATION..........................509
SELECTOR SWITCH
DESCRIPTION........................510
OPERATION..........................510
SHIFT MOTOR
DESCRIPTION........................511
OPERATION..........................511
REMOVAL............................511
INSTALLATION........................511
TRANSFER CASE - NV243
DESCRIPTION
The NV243 is an electronically controlled part-time
transfer case with a low range gear reduction system.
The NV243 has three operating ranges plus a NEU-
TRAL position. The low range system provides a gear
reduction ratio for increased low speed torque capa-
bility.
The geartrain is mounted in two aluminum case
halves attached with bolts. The mainshaft front and
rear bearings are mounted in aluminum retainer
housings bolted to the case halves.
OPERATING RANGES
Transfer case operating ranges are:
²2WD (2-wheel drive)
²4HI (4-wheel drive)
²4LO (4-wheel drive low range)
²NEUTRAL
The 2WD range is for use on any road surface at
any time.The 4HI and 4LO ranges are for off road use only.
They are not for use on hard surface roads. The only
exception being when the road surface is wet or slip-
pery or covered by ice and snow.
The low range reduction gear system is operative
in 4LO range only. This range is for extra pulling
power in off road situations. Low range reduction
ratio is 2.72:1.
SHIFT MECHANISM
Operating ranges are selected with a dash
mounted shift selector switch. The shift selector
switch provides a input to the Transfer Case Control
Module (TCCM) to indicate the driver's desire to
change operating ranges. The TCCM uses this input,
along with input from the transfer case mounted
mode sensor and information from the vehicle's bus,
to determine if a shift is permitted. If the TCCM
decides the shift is permitted, the TCCM controls the
shift motor, mounted to the exterior of the transfer
case, to perform the shift.
21 - 482 TRANSFER CASE - NV243DR

TRANSFER CASE - NV244 GENII
TABLE OF CONTENTS
page page
TRANSFER CASE - NV244 GENII
DESCRIPTION........................512
OPERATION..........................513
DIAGNOSIS AND TESTING - TRANSFER
CASE - NV244.......................513
REMOVAL............................514
DISASSEMBLY........................514
CLEANING...........................523
INSPECTION.........................523
ASSEMBLY...........................525
INSTALLATION........................534
SPECIFICATIONS
TRANSFER CASE - NV244 GENII........535
SPECIAL TOOLS
TRANSFER CASE - NV244 GENII........535
EXTENSION HOUSING SEAL
REMOVAL............................536
INSTALLATION........................536FLUID
STANDARD PROCEDURE - FLUID DRAIN AND
REFILL............................537
FRONT OUTPUT SHAFT SEAL
REMOVAL............................537
INSTALLATION........................538
MODE SENSOR
DESCRIPTION........................538
OPERATION..........................539
SELECTOR SWITCH
DESCRIPTION........................539
OPERATION..........................540
SHIFT MOTOR
DESCRIPTION........................541
OPERATION..........................541
REMOVAL............................541
INSTALLATION........................541
TRANSFER CASE - NV244
GENII
DESCRIPTION
The NV244 GENII is an electronically controlled
full and part-time transfer case with no two wheel
drive operation.
A differential in the transfer case is used to control
torque transfer to the front and rear axles. A low
range gear reduction system provides increased low
speed torque capability for off road operation. The
low range provides a 2.72:1 reduction ratio.
The geartrain is mounted in two aluminum case
halves attached with bolts. The mainshaft front and
rear bearings are mounted in aluminum retainer
housings bolted to the case halves.
OPERATING RANGES
NV244 GENII operating ranges are:
²AWD(All-Wheel Drive)
²4HI (Part-time)
²4LO
²NEUTRAL
The AWD mode can be used at any time and on
any road surface.The 4HI (Part-time) and 4LO ranges are for off
road use only. The only time these ranges can be
used is when the road surface is covered with snow,
ice, or other loose slippery material.
SHIFT MECHANISM
Operating ranges are selected with a dash
mounted shift selector switch. The shift selector
switch provides a input to the Transfer Case Control
Module (TCCM) to indicate the driver's desire to
change operating ranges. The TCCM uses this input,
along with the input from the transfer case mounted
mode sensor and information from the vehicle's bus,
to determine if a shift is permitted. If the TCCM
decides the shift is permitted, the TCCM controls the
shift motor, mounted to the exterior of the transfer
case, to perform the shift.
21 - 512 TRANSFER CASE - NV244 GENIIDR

TRANSFER CASE - NV273
TABLE OF CONTENTS
page page
TRANSFER CASE - NV273
DESCRIPTION........................542
OPERATION..........................543
DIAGNOSIS AND TESTING - TRANSFER
CASE - NV273.......................543
REMOVAL............................544
DISASSEMBLY........................544
CLEANING...........................554
INSPECTION.........................554
ASSEMBLY...........................556
INSTALLATION........................568
SPECIFICATIONS
TRANSFER CASE - NV273.............568
SPECIAL TOOLS
TRANSFER CASE NV271/NV273.........569
EXTENSION HOUSING SEAL AND DUST BOOT
REMOVAL............................571
INSTALLATION........................571FLUID
STANDARD PROCEDURE - FLUID DRAIN AND
REFILL............................571
FRONT OUTPUT SHAFT SEAL
REMOVAL............................572
INSTALLATION........................572
MODE SENSOR
DESCRIPTION........................573
OPERATION..........................573
SELECTOR SWITCH
DESCRIPTION........................574
OPERATION..........................574
SHIFT MOTOR
DESCRIPTION........................575
OPERATION..........................575
REMOVAL............................575
INSTALLATION........................575
TRANSFER CASE - NV273
DESCRIPTION
The NV273 is an electronically controlled part-time
transfer case with a low range gear reduction system.
The NV273 has three operating ranges plus a NEU-
TRAL position. The low range system provides a gear
reduction ratio for increased low speed torque capa-
bility.
The geartrain is mounted in two aluminum case
halves attached with bolts. The mainshaft front and
rear bearings are mounted in aluminum case halves.
OPERATING RANGES
Transfer case operating ranges are:
²2WD (2-wheel drive)
²4HI (4-wheel drive)
²4LO (4-wheel drive low range)
²NEUTRAL
The 2WD range is for use on any road surface at
any time.The 4HI and 4LO ranges are for off road use only.
They are not for use on hard surface roads. The only
exception being when the road surface is wet or slip-
pery or covered by ice and snow.
The low range reduction gear system is operative
in 4LO range only. This range is for extra pulling
power in off road situations. Low range reduction
ratio is 2.72:1.
SHIFT MECHANISM
Operating ranges are selected with a dash
mounted shift selector switch. The shift selector
switch provides a input to the Transfer Case Control
Module (TCCM) to indicate the driver's desire to
change operating ranges. The TCCM uses this input,
along with input from the transfer case mounted
mode sensor and information from the vehicle's bus,
to determine if a shift is permitted. If the TCCM
decides the shift is permitted, the TCCM controls the
shift motor, mounted to the exterior of the transfer
case, to perform the shift.
21 - 542 TRANSFER CASE - NV273DR

ADJUSTMENTS
ADJUSTMENT
(1) Locate access hole and remove the mylar tape
covering it. (Fig. 8)
(2) Insert a 5/32-inch hex-wrench through hole and
into adjustment screw. Loosen screw.
(3) Operate outside handle several times to release
any restriction because of mis-alignment.
(4) Tighten adjustment screw to 3 N´m (30 in.
lbs.).
(5) Test handle for proper operation.
LATCH STRIKER
REMOVAL
(1) Using a grease pencil or equivalent, mark the
position of the striker.
(2) Remove the bolts and remove the striker.
INSTALLATION
(1) Install the striker and install the bolts.
(2) Tighten the bolts to 28 N´m (21 ft. lbs.).
(3) Adjust the striker if needed. (Refer to 23 -
BODY/DOOR - FRONT/LATCH STRIKER - ADJUST-
MENTS)
ADJUSTMENTS
ADJUSTMENT
(1) Using a grease pencil or equivalent, mark the
position of the striker to aid in adjustment.
(2) Loosen the striker bolts.
(3) Change the striker position to adjust the rear
gap and flush measurement. (Refer to 23 - BODY/BODY STRUCTURE/GAP AND FLUSH - SPECIFI-
CATIONS)
(4) Tighten the bolts to 28 N´m (21 ft. lbs.).
TRIM PANEL
REMOVAL
(1) Remove the window crank, if equipped. (Fig.
10)
(2) Remove the interior handle. (Refer to 23 -
BODY/DOORS - REAR/INSIDE HANDLE ACTUA-
TOR - REMOVAL)
(3) Remove the screw near the inside handle. (Fig.
9)
CAUTION: Trim panel is attached to the door using
hooks molded into the panel. Do not pull the trim
panel straight off or damage to the panel and/or
power switch assembly may occur.
(4) Lift the trim panel up off the belt seal and
attachment hooks and separate the panel from the
door slightly.
(5) Disconnect the power window switch electrical
connector, if equipped, and remove the trim panel.
INSTALLATION
(1) Position the trim panel onto the lower hooks
and connect the power window switch electrical con-
nector, if equipped.
(2) Position the remaining trim panel attachment
hooks into the door panel and seat the trim panel
into the belt seal fully.
(3) Install the screw near the inside handle.
Fig. 8 LATCH ADJUSTMENT SCREW - TYPICAL
1 - DOOR LATCH
2 - MYLAR TAPE
3 - ADJUSTMENT SCREW
Fig. 9 TRIM PANEL
1 - DOOR
2 - ELECTRICAL CONNECTOR
3 - ATTACHMENT HOOKS
4 - SCREW
5 - TRIM PANEL
DRDOORS - REAR 23 - 33
LATCH (Continued)