DODGE RAM 2002 Service Manual Online

Fig. 20 GEAR TOOTH CONTACT PATTERNS
3 - 26 FRONT AXLE - 248FBIBR/BE
FRONT AXLE - 248FBI (Continued)

SPECIFICATIONS
FRONT AXLE - 248FBI
AXLE SPECIFICATIONS
DESCRIPTION SPECIFICATION
Axle Ratio 3.54, 4.10
Ring Gear Diameter 248 mm (9.75 in.)
Ring Gear Backlash 0.12-0.20 mm (0.005-0.008 in.)
Pinion Gear Standard Depth 127 mm (5.000 in.)
Pinion Bearing Preload - Original Bearing 1-2 N´m (10-20 in. lbs.)
Pinion Bearing Preload - New Bearing 2.26-4.52 N´m (20-40 in. lbs.)
TORQUE SPECIFICATIONS
DESCRIPTION N´m Ft. Lbs. In. Lbs.
Fill Hole Plug 34 25 -
Differential Cover Bolts 41 30 -
Bearing Cap Bolts 108 80 -
Ring Gear Bolts 176 130 -
Pinion Nut 292-678 215-496 -
Axle Nut 237 175 -
Shift Motor Bolts 11 8 96
SPECIAL TOOLS
FRONT AXLE
REMOVER - C-452
SPREADER - W-129-B
INSTALLER, BEARING - C-3095-A
WRENCH, FLANGE - C-3281
BR/BEFRONT AXLE - 248FBI 3 - 27
FRONT AXLE - 248FBI (Continued)

PILOTS, STUDS - C-3288-B
DIAL INDICATOR, SET - C-3339
INSTALLER, FLANGE - C-3718
HANDLE, DRIVE - C-4171
INSTALLER, BEARING - C-4190
INSTALLER, CUP - C-111
INSTALLER, CUP - C-146
REMOVER, CUP - D-158
REMOVER, CUP - D-162
PULLER/PRESS - C-293-PA
3 - 28 FRONT AXLE - 248FBIBR/BE
FRONT AXLE - 248FBI (Continued)

AXLE SHAFTS
REMOVAL
(1) Raise and support the vehicle.
(2) Remove wheel and tire assembly.
(3) Remove brake caliper, rotor and ABS wheel
speed sensor if equipped. Refer to 5 Brakes for pro-
cedures.
(4) Remove the cotter pin and axle hub nut.
(5) Remove hub bearing bolts (Fig. 21) and remove
hub bearing from the steering knuckle.
(6) Remove brake dust shield from knuckle.
(7) Remove axle shaft from the housing. Avoid
damaging the axle shaft oil seal.
INSTALLATION
(1) Clean axle shaft and apply a thin film of
Mopar Wheel Bearing Grease to the shaft splines,
seal contact surface, hub bore.
(2) Install axle shaft into the housing and differen-
tial side gears. Avoid damaging axle shaft oil seals in
the differential.
(3) Install dust shield and hub bearing on knuckle.
(4) Install hub bearing bolts and tighten to 170
N´m (125 ft. lbs.).
(5) Install axle washer and nut, tighten nut to 237
N´m (175 ft. lbs.). Align nut to next cotter pin hole
and install new cotter pin.
(6) Install ABS wheel speed sensor, brake rotor
and caliper. Refer to Brakes for proper procedures.
(7) Install wheel and tire assembly.
(8) Remove support and lower the vehicle.
BLOCK, ADAPTER ± C-239-37
BLOCK, ADAPTER ± C-239-62
HOLDER, YOKE - 6719A
PINION DEPTH, SET ± 6730
Fig. 21 HUB AND KNUCKLE
1 - KNUCKLE
2 - HUB BEARING
BR/BEFRONT AXLE - 248FBI 3 - 29
FRONT AXLE - 248FBI (Continued)

AXLE SHAFTS -
INTERMEDIATE
REMOVAL
(1) Remove vacuum shift motor housing.
(2) Remove outer axle shaft.
(3) Remove inner axle shaft seal from the shift
motor housing with a long drift or punch. Be careful
not to damage housing.
(4) Remove intermediate axle shaft and shift col-
lar.
(5) Assemble intermediate axle shaft bushing tools
(Fig. 22).
(6) Remove intermediate axle shaft bushing.
INSTALLATION - INTERMEDIATE AXLE
(1) Position the bushing on installation tool and
seat the bushing (Fig. 23) in the housing bore.
(2) Clean the inside perimeter of the axle shaft
tube with fine crocus cloth.
(3) Apply a light film of oil to the inside lip of the
new axle shaft seal.
(4) Install the inner axle seal (Fig. 24).
(5) Install the shift collar in the axle housing.
(6) Lubricate splined end of the intermediate axle
shaft with multi-purpose lubricant.
(7) Insert the intermediate axle shaft into the dif-
ferential side gear.CAUTION: Apply all-purpose lubricant to the axle
shaft splines to prevent damage to the seal during
axle shaft installation.
(8) Insert axle shaft into the tube and engage the
splined end of the shaft with the shift collar.
(9) Install the vacuum shift motor housing.
Fig. 22 INTERMEDIATE SHAFT BUSHING
1 - BUSHING
2 - SHIFT MOTOR HOUSING OPENING
3 - AXLE TUBE
4 - LOCATION FOR OPEN-END WRENCH
5 - SPECIAL TOOL 5041-2
6 - NUT
7 - SPECIAL TOOL 8417
8 - SPECIAL TOOL 8415
Fig. 23 BUSHING INSTALLATION
1 - SHIFT MOTOR HOUSING OPENING
2 - SPECIAL TOOL 5417
3 - SPECIAL TOOL 5041-2
4 - SPECIAL TOOL 8416
5 - BUSHING
Fig. 24 SEAL INSTALLATION
1 - SHIFT MOTOR HOUSING OPENING
2 - SEAL
3 - AXLE TUBE
4 - LOCATION FOR OPEN-END WRENCH
5 - SPECIAL TOOL 5041-2
6 - SPECIAL TOOL 8417
7 - SPECIAL TOOL 8411
3 - 30 FRONT AXLE - 248FBIBR/BE

AXLE SHAFT SEALS
REMOVAL
(1) Remove hub bearings and axle shafts.
(2) Remove axle shaft seal from the differential
housing with a long drift or punch.Be careful not
to damage housing.
(3) Clean the inside perimeter of the differential
housing with fine crocus cloth.
INSTALLATION
(1) Apply a light film of oil to the inside lip of the
new axle shaft seal.
(2) Install the inner axle seal (Fig. 25).
(3) Install axles and hub bearings.
AXLE VACUUM MOTOR
DESCRIPTION
The disconnect axle control system consists of:
²Shift motor.
²Indicator switch.
²Vacuum switch.
²Vacuum harness (Fig. 26).
OPERATION
The shift motor receives a vacuum signal from the
switch mounted on the transfer case when the vehi-
cle operator wants to switch from two wheel drive
mode to four wheel drive mode, or vice versa. When
this signal is received, the shift motor begins to move
the shift fork and collar within the axle housing. In
the four wheel drive mode, the shift collar connects
the axle intermediate shaft to the axle shaft to sup-
ply engine power to both front wheels. In two wheel
drive mode, the shift collar is disengaged from the
intermediate shaft and the intermediate shaft is
allowed to free-spin. When the two shafts are disen-
gaged, the load on the engine is reduced, thereby pro-
viding better fuel economy and road handling.
Fig. 25 SEAL INSTALLATION
1 - DIFFERENTIAL HOUSING
2 - POSITION FOR OPEN-END WRENCH
3 - SPECIAL TOOL 5041-2
4 - SPECIAL TOOL 8417
5 - SEAL
6 - SPECIAL TOOL 8411
Fig. 26 VACUUM CONTROL SYSTEM
1 - CHECK VALVE
2 - CONTROL SWITCH ON TRANSFER CASE
3 - AIR VENT FILTER
4 - AXLE SHIFT MOTOR
5 - INDICATOR SWITCH
BR/BEFRONT AXLE - 248FBI 3 - 31

DIAGNOSIS AND TESTING - VACUUM MOTOR
AXLE VACUUM SHIFT MOTOR
3 - 32 FRONT AXLE - 248FBIBR/BE
AXLE VACUUM MOTOR (Continued)

AXLE VACUUM SHIFT MOTOR (CONT'D)
BR/BEFRONT AXLE - 248FBI 3 - 33
AXLE VACUUM MOTOR (Continued)

REMOVAL
(1) Disconnect the vacuum and wiring connector
from the shift housing.
(2) Remove indicator switch.
(3) Remove shift motor housing cover, gasket and
shield from the housing (Fig. 27).
DISASSEMBLY
(1) Remove E-clips from the shift motor housing
and shaft. Remove shift motor and shift fork from
the housing (Fig. 28).
(2) Remove O-ring seal from the shift motor shaft.
(3) Clean and inspect all components. Replaced
any component that is excessively worn or damaged.
ASSEMBLY
(1) Install a new O-ring seal on the shift motor
shaft.
(2) Insert shift motor shaft through the hole in the
housing and shift fork. The shift fork offset should be
toward the differential.
(3) Install E-clips on the shift motor shaft and
housing.
INSTALLATION
(1) Install shift motor housing gasket.
(2) Guide the shift fork onto the shift collar groove,
while install the shift motor housing cover.
(3) Install shift motor housing shield and tighten
the bolts to 11 N´m (96 in. lbs.).(4) Add 148 ml (5 ounces) of API grade GL 5
hypoid gear lubricant to the shift motor housing. Add
lubricant through indicator switch mounting hole.
(5) Install indicator switch, electrical connector
and vacuum harness.
SINGLE CARDAN UNIVERSAL
JOINTS
REMOVAL
Single cardan U-joint components are not service-
able. If defective they must be replaced as a unit.
CAUTION: Clamp only the narrow forged portion of
the yoke in the vise. To avoid distorting the yoke,
do not over tighten the vise jaws.
(1) Remove axle shaft.
(2) Remove the bearing cap retaining snap rings
(Fig. 29).
NOTE: Saturate the bearing caps with penetrating
oil prior to removal.
(3) Locate a socket with an inside diameter is
larger than the bearing cap. Place the socket (receiv-
er) against the yoke and around the perimeter of the
bearing cap to be removed.
(4) Locate a socket with an outside diameter is
smaller than the bearing cap. Place the socket (driv-
er) against the opposite bearing cap.
Fig. 27 SHIFT MOTOR HOUSING
1 - INDICATOR LAMP SWITCH
2 - DISCONNECT HOUSING
3 - VACUUM SHIFT MOTOR
4 - AXLE SHAFT
5 - SEAL
6 - SHIFT COLLAR
7 - SHIFT FORK
8 - BEARING
9 - INTERMEDIATE AXLE SHAFT
Fig. 28 SHIFT MOTOR COMPONENTS
1 - INDICATOR SWITCH
2 - E-CLIP
3 - O-RING
4 - SHIFT MOTOR
5 - SHIFT FORK
6 - VACUUM PORTS
7 - DISCONNECT HOUSING AND GASKET
3 - 34 FRONT AXLE - 248FBIBR/BE
AXLE VACUUM MOTOR (Continued)

(5) Position the yoke with the sockets in a vise
(Fig. 30).
(6) Tighten the vise jaws to force the bearing cap
into the larger socket (receiver).
(7) Release the vise jaws. Remove the sockets and
bearing cap that was partially forced out of the yoke.
(8) Repeat the above procedure for the remaining
bearing cap and remove spider from the propeller
shaft yoke.
INSTALLATION
(1) Pack the bearing caps 1/3 full of wheel bearing
lubricant. Apply extreme pressure (EP), lithium-base
lubricant to aid in installation.
(2) Position the spider in the yoke. Insert the seals
and bearings. Tap the bearing caps into the yoke
bores far enough to hold the spider in position.
(3) Place the socket (driver) against one bearing
cap. Position the yoke with the socket in a vise.
(4) Tighten the vise to force the bearing caps into
the yoke. Force the caps enough to install the retain-
ing clips.
(5) Install the bearing cap retaining clips.
(6) Install axle shaft.
PINION SEAL
REMOVAL
(1) Raise and support the vehicle.
(2) Remove wheel and tire assemblies.
(3) Remove brake calipers and rotors
(4) Mark the propeller shaft and pinion yoke for
installation reference.
(5) Remove the propeller shaft from the yoke.
(6) Rotate the pinion gear three or four times.
(7) Measure the amount of torque necessary to
rotate the pinion gear with a (in. lbs.) dial-type
torque wrench. Record the torque reading for instal-
lation reference.
(8) Remove the pinion yoke nut and washer. Use
Remover C-452 and Wrench C-3281 to remove the
pinion yoke (Fig. 31) .
(9) Use suitable pry tool or slide hammer mounted
screw to remove the pinion shaft seal.
INSTALLATION
(1) Apply a light coating of gear lubricant on the
lip of pinion seal. Install seal with an appropriate
installer (Fig. 32).
(2) Install yoke on the pinion gear with Installer
C-3718 and Holder 6719 (Fig. 33).
CAUTION: Do not exceed the minimum tightening
torque when installing the pinion yoke retaining
nut. Damage to collapsible spacer or bearings may
result.
Fig. 29 AXLE SHAFT OUTER U-JOINT
1 - SHAFT YOKE
2 - BEARING CAP
3 - SNAP RINGS
4 - BEARING CAP
5 - SPINDLE YOKE
6 - BEARING
7 - BEARING CAP
8 - SNAP RINGS
9 - BEARING CAP
Fig. 30 YOKE BEARING CAP
1 - LARGE-DIAMETER SOCKET WRENCH
2 - VISE
3 - SMALL-DIAMETER SOCKET WRENCH
BR/BEFRONT AXLE - 248FBI 3 - 35
SINGLE CARDAN UNIVERSAL JOINTS (Continued)