1998 DODGE RAM 1500 control arm

MAP SENSOR
DESCRIPTION
A combination, dual function Intake Manifold Air
Temperature Sensor/MAP Sensor is used. Refer to
Intake Air Temperature Sensor/MAP Sensor for infor-
mation.
THROTTLE CONTROL CABLE
REMOVAL
If Equipped With Engine Mounted Accelerator Pedal
Position Sensor
(1) Disconnect both negative battery cables at both
batteries.
(2) From inside vehicle, hold up accelerator pedal.
Remove plastic cable retainer and throttle cable core
wire from upper end of pedal arm (Fig. 32). The plas-
tic cable retainer snaps into pedal arm.
(3) From inside vehicle, remove cable clip (Fig. 32).
(4) Remove cable core wire at pedal arm.
(5) Remove cable housing from dash panel and
pull cable into engine compartment.
(6) Remove cable cover (Fig. 33). Cable cover is
attached with 2 Phillips screws, 2 plastic retention
clips and 2 push tabs (Fig. 33). Remove 2 Phillips
screws and carefully pry out 2 retention clips. After
clip removal, push rearward on front tab, and
upward on lower tab for cover removal.
(7) Using 2 screwdrivers, pry cable connector
socket from throttle lever ball (Fig. 34).Be very
careful not to bend throttle lever arm.
If Equipped With Battery Tray Mounted Accelerator Pedal
Position Sensor
The Throttle Control Cable connects the accelera-
tor pedal to the Accelerator Pedal Position Sensor
(APPS). A separate mechanical cable is not routed to
the throttle body.
CAUTION: Be careful not to damage or kink cable
core wire (within cable sheathing) while servicing
accelerator pedal, cables or APPS.
(1) Disconnect both negative battery cables at both
batteries.
(2) From inside vehicle, hold up accelerator pedal.
Remove plastic cable retainer and throttle cable core
wire from upper end of pedal arm (Fig. 35). The plas-
tic cable retainer snaps into pedal arm.
(3) Remove cable core wire at pedal arm.
(4) Remove APPS. Refer to (Diesel) Accelerator
Pedal Position Sensor (APPS) Removal / Installation.
(5) From inside vehicle, remove cable clip (Fig. 35).
Fig. 30 INTAKE/MAP SENSOR
1 - TOP OF INTAKE MANIFOLD
2 - IAT/MAP SENSOR
3 - ELEC. CONNECTOR
4 - MOUNTING BOLTS (2)
Fig. 31 SENSOR O-RING
1 - IAT/MAP SENSOR
2 - O-RING
DRFUEL INJECTION - DIESEL 14 - 83
INTAKE AIR TEMPERATURE SENSOR/MAP SENSOR (Continued)

(6) Remove cable housing from dash panel and
pull cable into engine compartment.
(7) Remove cable housing at APPS bracket by
pressing on release tab with a small screwdriver.Toprevent cable housing breakage, press on tab
only enough to release cable from APPS
bracket.
INSTALLATION
Accelerator Pedal Position Sensor Mounted To Engine
(1) Install cable through mounting hole on cable
mounting bracket (Fig. 34). Cable snaps into bracket.
Be sure 2 pinch tabs are secure.
(2) Using large pliers, connect cable end socket to
throttle lever ball (snaps on).
(3) Install remaining cable housing end into and
through dash panel opening (snaps into position).
The two plastic pinch tabs should lock cable to dash
panel.
(4) From inside vehicle, hold up accelerator pedal.
Install throttle cable core wire and plastic cable
retainer into and through upper end of pedal arm
(the plastic retainer is snapped into pedal arm).
When installing plastic retainer to accelerator pedal
arm, note index tab on pedal arm (Fig. 32). Align
index slot on plastic cable retainer to this index tab.
(5) Connect negative battery cables to both batter-
ies.
(6) Before starting engine, operate accelerator
pedal to check for any binding.
(7) Install cable/lever cover.
Fig. 32 ACCELERATOR PEDAL MOUNTING
1 - ACCELERATOR CABLE
2 - PLASTIC RETAINER (CLIP)
3 - THROTTLE PEDAL ARM
4 - PEDAL / BRACKET ASSEMBLY
5 - CABLE CLIP
Fig. 33 CABLE/LEVER/THROTTLE LINKAGE COVER
1 - CABLE/LEVER/LINKAGE COVER
2 - PUSH UP LOWER TAB
3 - SCREWS/CLIPS (2)
4 - TAB PUSH HERE
Fig. 34 SERVO CABLE AT THROTTLE LEVER
1 - PINCH (2) TABS
2 - CABLE MOUNTING BRACKET
3 - PINCH TABS (2)
4 - OFF
5 - THROTTLE CABLE
6 - THROTTLE LEVER
7 - THROTTLE LEVER PIN
8 - OFF
9 - CONNECTOR
10 - SPEED CONTROL CABLE
14 - 84 FUEL INJECTION - DIESELDR
THROTTLE CONTROL CABLE (Continued)

Accelerator Pedal Position Sensor Not Mounted To Engine
(1) Attach cable to Accelerator Pedal Position Sen-
sor (APPS). Refer to APPS (Diesel) Removal / Instal-
lation.
(2) Push cable housing into rubber grommet and
through opening in dash panel.
(3) From inside vehicle, install clip holding cable
to dashpanel (Fig. 35).
(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
Engine Control Module (ECM).
PTO SWITCH
DESCRIPTION
This Engine Control Module (ECM) input is used
only on models equipped with aftermarket Power
Take Off (PTO) units.
OPERATION
This input is used only to tell the PCM (non-die-
sel), or ECM (diesel) that the aftermarket PTO
(Power Take Off) unit has been engaged. The PCM
(or ECM) will disable (temporarily shut down) cer-
tain OBD II diagnostic trouble codes when the PTO
unit is engaged.
Fig. 35 ACCELERATOR PEDAL MOUNTING
1 - ACCELERATOR CABLE
2 - PLASTIC RETAINER (CLIP)
3 - THROTTLE PEDAL ARM
4 - PEDAL / BRACKET ASSEMBLY
5 - CABLE CLIP
DRFUEL INJECTION - DIESEL 14 - 85
THROTTLE CONTROL CABLE (Continued)

INSTALLATION
NOTE: Before installing gear inspect bushings and
replace if worn or damaged.
NOTE: In the frame there is two holes for the
mounting of the steering gear one is slotted and
one is round, When tightening the gear to specifi-
cations make sure to tighten the mounting bolt with
the hole first to avoided movement of the steering
gear.
(1) Install the gear on the front crossmember and
tighten the mounting bolts to 319 N´m (235 ft. lbs.).
(Fig. 4) & (Fig. 3).
(2) Slide the shaft coupler onto the gear. Install
newpinch bolt and tighten to 49 N´m (36 ft. lbs.).
(3) Clean and dry the tie rod end studs and the
knuckle tapers.
(4) Install the tie rod ends into the steering knuck-
les and tighten the nuts to 61 N´m (45 ft. lbs.) thenan additional 90É. (Refer to 19 - STEERING/LINK-
AGE/TIE ROD END - INSTALLATION).
(5) Install the pressure power steering hose to the
steering gear and tighten to 32 N´m (23 ft. lbs.).
(Refer to 19 - STEERING/PUMP/HOSES - INSTAL-
LATION).
(6) Install the return power steering hose to the
steering gear and tighten to 71 N´m (52 ft. lbs.).
(Refer to 19 - STEERING/PUMP/HOSES - INSTAL-
LATION).
(7) Install the front skid plate (Refer to 13 -
FRAME & BUMPERS/FRAME/FRONT SKID PLATE
- INSTALLATION).
(8) Install the tire and wheel assembly (Refer to 22
- TIRES/WHEELS/WHEELS - STANDARD PROCE-
DURE).
(9) Remove the support and lower the vehicle.
(10) Fill the system with fluid, (Refer to 19 -
STEERING/PUMP - STANDARD PROCEDURE).
(11) Adjust the toe position. (Refer to 2 - SUSPEN-
SION/WHEEL ALIGNMENT - STANDARD PROCE-
DURE).
Fig. 3 STEERING GEAR 4X2
1-SWAYBAR
2 - STEERING GEAR
3 - LEFT OUTER TIE ROD END
4 - LOWER CONTROL ARMS
5 - LEFT INNER & RIGHT OUTER (TIE ROD ENDS)
Fig. 4 STEERING GEAR 4X4
1 - FRONT AXLE
2 - STEERING GEAR MOUNTING NUTS & BUSHINGS
19 - 18 GEAR - INDEPENDENT FRONT SUSPENSIONDR
GEAR - INDEPENDENT FRONT SUSPENSION (Continued)

LINKAGE - INDEPENDENT FRONT SUSPENSION
TABLE OF CONTENTS
page page
LINKAGE - INDEPENDENT FRONT
SUSPENSION
DIAGNOSIS AND TESTING - OUTER TIE ROD
END ................................32TIE ROD END
REMOVAL - OUTER TIE ROD END..........32
INSTALLATION - OUTER TIE ROD END......33
LINKAGE - INDEPENDENT
FRONT SUSPENSION
DIAGNOSIS AND TESTING - OUTER TIE ROD
END
NOTE: If the outer tie rod end is equipped with a
lubrication fitting, grease the joint then road test
the vehicle before performing test.
(1) Raise the front of the vehicle. Place safety floor
stands under both lower control arms as far outboard
as possible. Lower the vehicle to allow the stands to
support some or all of the vehicle weight.
(2) Remove the front tires.
(3) Mount a dial indicator solidly to the vehicle
steering knuckle and then zero the dial indicator.
(4) Position indicator plunger on the topside of the
outer tie rod end.
NOTE: The dial indicator plunger must be perpen-
dicular to the machined surface of the outer tie rod
end.
(5) Position a pry bar in order to pry downwards
on the outer tie rod end.
(6) If the travel exceeds 0.5 mm (0.020 in.), replace
the outer tie rod end (Refer to 19 - STEERING/
LINKAGE/TIE ROD END - REMOVAL).
(7) If the outer tie rod end is within specs reinstall
the front tires (Refer to 22 - TIRES/WHEELS/
WHEELS - STANDARD PROCEDURE).
TIE ROD END
REMOVAL - OUTER TIE ROD END
NOTE: Do not twist the boot anytime during
removal or installation.
(1) Loosen the jam nut.
(2) Remove the outer tie rod end nut from the ball
stud.
(3) Separate the tie rod ball stud from the knuckle
with Remover 8677 (Fig. 1).
(4) Unthread the outer tie rod end from the inner
tie rod.
Fig. 1 TIE ROD SEPARATION
1 - TIE ROD END
2 - SPECIAL TOOL 8677
19 - 32 LINKAGE - INDEPENDENT FRONT SUSPENSIONDR

IDENTIFICATION
Transmission identification numbers are stamped
on the left side of the case just above the oil pan gas-
ket surface (Fig. 2). Refer to this information when
ordering replacement parts.
GEAR RATIOS
The 48RE gear ratios are:
1st.................................2.45:1
2nd................................1.45:1
3rd................................1.00:1
4th.................................0.69:1
Rev.................................2.20:1
OPERATION
The application of each driving or holding compo-
nent is controlled by the valve body based upon the
manual lever position, throttle pressure, and gover-
nor pressure. The governor pressure is a variable
pressure input to the valve body and is one of the
signals that a shift is necessary. First through fourth
gear are obtained by selectively applying and releas-
ing the different clutches and bands. Engine power is
thereby routed to the various planetary gear assem-
blies which combine with the overrunning clutch
assemblies to generate the different gear ratios. The
torque converter clutch is hydraulically applied and
is released when fluid is vented from the hydraulic
circuit by the torque converter control (TCC) solenoid
on the valve body. The torque converter clutch is con-
trolled by the Powertrain Control Module (PCM). The
torque converter clutch engages in fourth gear, and
in third gear under various conditions, such as when
the O/D switch is OFF, when the vehicle is cruising
on a level surface after the vehicle has warmed up.
The torque converter clutch can also be engaged in
the MANUAL SECOND gear position if high trans-
mission temperatures are sensed by the PCM. The
torque converter clutch will disengage momentarily
when an increase in engine load is sensed by the
PCM, such as when the vehicle begins to go uphill or
the throttle pressure is increased. The torque con-
verter clutch feature increases fuel economy and
reduces the transmission fluid temperature.
Since the overdrive clutch is applied in fourth gear
only and the direct clutch is applied in all ranges
except fourth gear, the transmission operation for
park, neutral, and first through third gear will be
described first. Once these powerflows are described,
the third to fourth shift sequence will be described.
1 - TORQUE CONVERTER 10 - OVERDRIVE CLUTCH
2 - INPUT SHAFT 11 - DIRECT CLUTCH
3 - OIL PUMP 12 - PLANETARY GEAR
4 - FRONT BAND 13 - INTERMEDIATE SHAFT
5 - FRONT CLUTCH 14 - OVERDRIVE OVERRUNNING CLUTCH
6 - REAR CLUTCH 15 - DIRECT CLUTCH SPRING
7 - PLANETARIES 16 - OVERDRIVE PISTON RETAINER
8 - REAR BAND 17 - OIL PAN
9 - OVERRUNNING CLUTCH 18 - VALVE BODY
Fig. 2 Transmission Part Number And Serial
Number Location
1 - PART NUMBER
2 - BUILD DATE
3 - SERIAL NUMBER
21 - 134 AUTOMATIC TRANSMISSION - 48REDR
AUTOMATIC TRANSMISSION - 48RE (Continued)

DIAGNOSIS CHARTS
CONDITION POSSIBLE CAUSES CORRECTION
HARSH ENGAGEMENT
(FROM NEUTRAL TO
DRIVE OR REVERSE)1. Fluid Level Low. 1. Add Fluid
2. Throttle Linkage Mis-adjusted. 2. Adjust linkage - setting may be too long.
3. Mount and Driveline Bolts Loose. 3. Check engine mount, transmission
mount, propeller shaft, rear spring to body
bolts, rear control arms, crossmember and
axle bolt torque. Tighten loose bolts and
replace missing bolts.
4. U-Joint Worn/Broken. 4. Remove propeller shaft and replace
U-Joint.
5. Axle Backlash Incorrect. 5. Check per Service Manual. Correct as
needed.
6. Hydraulic Pressure Incorrect. 6. Check pressure. Remove, overhaul or
adjust valve body as needed.
7. Band Mis-adjusted. 7. Adjust rear band.
8. Valve Body Check Balls Missing. 8. Inspect valve body for proper check ball
installation.
9. Axle Pinion Flange Loose. 9. Replace nut and check pinion threads
before installing new nut. Replace pinion
gear if threads are damaged.
10. Clutch, band or planetary
component damaged.10. Remove, disassemble and repair
transmission as necessary.
11. Converter Clutch Faulty. 11. Replace converter and flush cooler and
line before installing new converter.
21 - 146 AUTOMATIC TRANSMISSION - 48REDR
AUTOMATIC TRANSMISSION - 48RE (Continued)

BTSI FUNCTION CHECK
(1) Verify removal of ignition key allowed in PARK
position only.
(2) When the shift lever is in PARK, the ignition
key cylinder should rotate freely from off to lock.
When the shifter is in any other position, the ignition
key should not rotate from off to lock.
(3) Shifting out of PARK should be possible when
the ignition key cylinder is in the off position.
(4) Shifting out of PARK should not be possible
while applying normal force, and ignition key cylin-
der is in the run or start positions, unless the foot
brake pedal is depressed approximately 1/2 inch
(12mm).
(5) Shifting out of PARK should not be possible
when the ignition key cylinder is in the accessory or
lock position.
(6) Shifting between any gear and NEUTRAL, or
PARK, may be done without depressing foot brake
with ignition switch in run or start positions.
(7) Engine starts must be possible with shifter
lever in PARK or NEUTRAL positions only. Engine
starts must not be possible in any position other than
PARK or NEUTRAL.
(8) With shifter lever in the:
²PARK position - Apply upward force on the shift
arm and remove pressure. Engine starts must be
possible.²PARK position - Apply downward force on the
shift arm and remove pressure. Engine starts must
be possible.
²NEUTRAL position - Normal position. Engine
starts must be possible.
²NEUTRAL position - Engine running and brakes
applied, apply upward force on the shift arm. Trans-
mission shall not be able to shift from neutral to
reverse.
ELECTRONIC GOVERNOR
DESCRIPTION
Governor pressure is controlled electronically. Com-
ponents used for governor pressure control include:
²Governor body
²Valve body transfer plate
²Governor pressure solenoid valve
²Governor pressure sensor
²Fluid temperature thermistor
²Throttle position sensor (TPS)
²Transmission speed sensor
²Powertrain control module (PCM)
GOVERNOR PRESSURE SOLENOID VALVE
The solenoid valve is a duty-cycle solenoid which
regulates the governor pressure needed for upshifts
and downshifts. It is an electro-hydraulic device
located in the governor body on the valve body trans-
fer plate (Fig. 76).
Fig. 75 Brake Transmission Interlock Mechanism
1 - STEERING COLUMN
2 - GEARSHIFT CABLE
3 - GEARSHIFT CABLE LOCK TAB
4 - BTSI SOLENOID LOCK TAB
5 - BTSI CONNECTOR
Fig. 76 Governor Pressure Solenoid Valve
1 - SOLENOID FILTER
2 - GOVERNOR PRESSURE SOLENOID
DRAUTOMATIC TRANSMISSION - 48RE 21 - 197
BRAKE TRANSMISSION SHIFT INTERLOCK SYSTEM (Continued)