2001 DODGE RAM torque

(11) Install yoke washer and anewnut on the
pinion gear. Tighten the nut to 258 N´m (190 ft. lbs.)
minimum.Do not over-tighten.Maximum torque is
393 N´m (290 ft. lbs.).
CAUTION: Never loosen pinion gear nut to decrease
pinion gear bearing preload torque and never
exceed specified preload torque. If preload torque
is exceeded a new collapsible spacer must be
installed.
(12) Use Yoke Holder 6719A to hold the yoke (Fig.
61) and tighten the nut in 6.8 N´m (5 ft. lbs.) until
the rotating torque is achieved. Measure the preload
torque frequently to avoid over-tightening the nut.
(13) Check bearing preload torque with an inch
pound torque wrench (Fig. 62). The torque necessary
to rotate the pinion gear should be:
²Original Bearings: 1 to 3 N´m (10 to 20 in. lbs.).
²New Bearings: 2 to 5 N´m (15 to 35 in. lbs.).
(14) Invert differential case in a vise and start two
ring gear bolts. This will provide case-to-ring gear
bolt hole alignment.
(15) Installnewring gear bolts and alternately
tighten to 108 N´m (80 ft. lbs.). (Fig. 63).
CAUTION: Do not reuse the bolts that held the ring
gear to the differential case. The bolts can fracture
causing extensive damage.
(16) Install differential in axle housing and verify
gear mesh and contact pattern. Refer to Adjustments
(Gear Contact Pattern).
(17) Install differential cover and fill with lubri-
cant.(18) Install propeller shaft with reference marks
aligned.
(19) Remove support and lower vehicle.
Fig. 61 Tightening Pinion Nut
1 - PINION FLANGE
2 - YOKE HOLDING
3 - DIFFERENTIAL HOUSING
Fig. 62 Pinion Rotating Torque
1 - PINION YOKE
2 - INCH POUND TORQUE WRENCH
Fig. 63 Ring Gear Bolt
1 - TORQUE WRENCH
2 - RING GEAR BOLT
3 - RING GEAR
4 - CASE
3 - 44 FRONT AXLE - 216FBIBR/BE
PINION GEAR/RING GEAR (Continued)

mate and side gears. The side gears are splined to
the axle shafts.
During straight-ahead driving, the differential pin-
ion gears do not rotate on the pinion mate shaft. This
occurs because input torque applied to the gears is
divided and distributed equally between the two side
gears. As a result, the pinion gears revolve with the
pinion mate shaft but do not rotate around it (Fig. 2).When turning corners, the outside wheel must
travel a greater distance than the inside wheel to
complete a turn. The difference must be compensated
for to prevent the tires from scuffing and skidding
through turns. To accomplish this, the differential
allows the axle shafts to turn at unequal speeds (Fig.
3). In this instance, the input torque applied to the
pinion gears is not divided equally. The pinion gears
now rotate around the pinion mate shaft in opposite
directions. This allows the side gear and axle shaft
attached to the outside wheel to rotate at a faster
speed.
DIAGNOSIS AND TESTING - AXLE
GEAR NOISE
Axle gear noise can be caused by insufficient lubri-
cant, incorrect backlash, tooth contact, worn/damaged
gears or the carrier housing not having the proper
offset and squareness.
Gear noise usually happens at a specific speed
range. The noise can also occur during a specific type
of driving condition. These conditions are accelera-
tion, deceleration, coast, or constant load.
When road testing, first warm-up the axle fluid by
driving the vehicle at least 5 miles and then acceler-
ate the vehicle to the speed range where the noise is
the greatest. Shift out-of-gear and coast through the
peak-noise range. If the noise stops or changes
greatly:
²Check for insufficient lubricant.
²Incorrect ring gear backlash.
²Gear damage.
Differential side gears and pinions can be checked
by turning the vehicle. They usually do not cause
noise during straight-ahead driving when the gears
are unloaded. The side gears are loaded during vehi-
Fig. 1 248 FBI Differential Cover
1 - FILL PLUG
2 - MODEL NUMBER
3 - RATIO TAG
4 - DIFFERENTIAL COVER
Fig. 2 Differential Operation-Straight Ahead Driving
1 - IN STRAIGHT AHEAD DRIVING EACH WHEEL ROTATES AT
100% OF CASE SPEED
2 - PINION GEAR
3 - SIDE GEAR
4 - PINION GEARS ROTATE WITH CASE
Fig. 3 Differential Operation-On Turns
1 - PINION GEARS ROTATE ON PINION SHAFT
3 - 46 FRONT AXLE - 248FBIBR/BE
FRONT AXLE - 248FBI (Continued)

Condition Possible Causes Correction
Loss Of Lubricant 1. Lubricant level too high. 1. Drain lubricant to the correct level.
2. Worn axle shaft seals. 2. Replace seals.
3. Cracked differential housing. 3. Repair as necessary.
4. Worn pinion seal. 4. Replace seal.
5. Worn/scored yoke. 5. Replace yoke and seal.
6. Axle cover not properly sealed. 6. Remove, clean, and re-seal cover.
Axle Overheating 1. Lubricant level low. 1. Fill differential to correct level.
2. Improper grade of lubricant. 2. Fill differential with the correct fluid
type and quantity.
3. Bearing pre-loads too high. 3. Re-adjust bearing pre-loads.
4. Insufficient ring gear backlash. 4. Re-adjust ring gear backlash.
Gear Teeth Broke 1. Overloading. 1. Replace gears. Examine other gears
and bearings for possible damage.
2. Erratic clutch operation. 2. Replace gears and examine the
remaining parts for damage. Avoid
erratic clutch operation.
3. Ice-spotted pavement. 3. Replace gears and examine
remaining parts for damage.
4. Improper adjustments. 4. Replace gears and examine
remaining parts for damage. Ensure ring
gear backlash is correct.
Axle Noise 1. Insufficient lubricant. 1. Fill differential with the correct fluid
type and quantity.
2. Improper ring gear and pinion
adjustment.2. Check ring gear and pinion contact
pattern.
3. Unmatched ring gear and pinion. 3. Replace gears with a matched ring
gear and pinion.
4. Worn teeth on ring gear and/or
pinion.4. Replace ring gear and pinion.
5. Loose pinion bearings. 5. Adjust pinion bearing pre-load.
6. Loose differential bearings. 6. Adjust differential bearing pre-load.
7. Mis-aligned or sprung ring gear. 7. Measure ring gear run-out. Replace
components as necessary.
8. Loose differential bearing cap bolts. 8. Inspect differential components and
replace as necessary. Ensure that the
bearing caps are torqued tot he proper
specification.
9. Housing not machined properly. 9. Replace housing.
BR/BEFRONT AXLE - 248FBI 3 - 49
FRONT AXLE - 248FBI (Continued)

REMOVAL
(1) Raise and support the vehicle.
(2) Remove the wheels and tires.
(3) Remove the brake calipers and rotors. Refer to
Group 5, Brakes, for proper procedures.
(4) Remove ABS wheel speed sensors, if equipped.
Refer to Group 5, Brakes, for proper procedures.
(5) Disconnect the axle vent hose.
(6) Disconnect vacuum hose and electrical connec-
tor at disconnect housing.
(7) Remove the front propeller shaft.
(8) Disconnect the stabilizer bar links at the axle
brackets.
(9) Disconnect the shock absorbers from axle
brackets.
(10) Disconnect the track bar from the axle
bracket.
(11) Disconnect the tie rod and drag link from the
steering knuckles.
(12) Position the axle with a suitable lifting device
under the axle assembly.
(13) Secure axle to lifting device.
(14) Mark suspension alignment cams for installa-
tion reference.
(15) Disconnect the upper and lower suspension
arms from the axle bracket.
(16) Lower the axle. The coil springs will drop
with the axle.
(17) Remove the coil springs from the axle bracket.
INSTALLATION
CAUTION: Suspension components with rubber
bushings should be tightened with the weight of the
vehicle on the suspension, at normal height. If
springs are not at their normal ride position, vehicle
ride comfort could be affected and premature bush-
ing wear may occur. Rubber bushings must never
be lubricated.
(1) Support the axle on a suitable lifting device.
(2) Secure axle to lifting device.
(3) Position the axle under the vehicle.
(4) Install the springs, retainer clip and bolts.
(5) Raise the axle and align it with the spring
pads.
(6) Position the upper and lower suspension arms
in the axle brackets. Install bolts, nuts and align the
suspension alignment cams to the reference marks.
Do not tighten at this time.
(7) Connect the track bar to the axle bracket and
install the bolt. Do not tighten at this time.
(8) Install the shock absorber and tighten bolts to
121 N´m (89 ft. lbs.) torque.(9) Install the stabilizer bar link to the axle
bracket. Tighten the nut to 37 N´m (27 ft. lbs.)
torque.
(10) Install the drag link and tie rod to the steer-
ing knuckles and tighten the nuts to 88 N´m (65 ft.
lbs.) torque.
(11) Install the ABS wheel speed sensors, if
equipped. Refer to group 5, Brakes, for proper proce-
dures.
(12) Install the brake calipers and rotors. Refer to
Group 5, Brakes, for proper procedures.
(13) Connect the vent hose to the tube fitting.
(14) Connect vacuum hose and electrical connector
to disconnect housing.
(15) Install front propeller shaft.
(16) Check and add differential lubricant, if neces-
sary. Refer to Lubricant Specifications in this section
for lubricant requirements.
(17) Install the wheel and tire assemblies.
(18) Remove the supports and lower the vehicle.
(19) Tighten the upper suspension arm nuts at
axle to 121 N´m (89 ft. lbs.) torque. Tighten the
upper suspension arm nuts at frame to 84 N´m (62 ft.
lbs.) torque.
(20) Tighten the lower suspension arm nuts at
axle to 84 N´m (62 ft. lbs.) torque. Tighten the lower
suspension arm nuts at frame to 119 N´m (88 ft. lbs.)
torque.
(21) Tighten the track bar bolt at the axle bracket
to 176 N´m (130 ft. lbs.) torque.
(22) Check the front wheel alignment.ADJUSTMENTS
Ring and pinion gears are supplied as matched
sets only. The identifying numbers for the ring and
pinion gear are etched into the face of each gear (Fig.
4). A plus (+) number, minus (±) number or zero (0) is
etched into the face of the pinion gear. This number
is the amount (in thousandths of an inch) the depth
varies from the standard depth setting of a pinion
etched with a (0). The standard setting from the cen-
ter line of the ring gear to the back face of the pinion
is 127 mm (5.00 in.). The standard depth provides
the best gear tooth contact pattern. Refer to Back-
lash and Contact Pattern in this section for addi-
tional information.
Compensation for pinion depth variance is
achieved with a select shim/oil baffle. The shims are
placed between the rear pinion bearing and the pin-
ion gear head (Fig. 5).
If a new gear set is being installed, note the depth
variance etched into both the original and replace-
ment pinion. Add or subtract this number from the
thickness of the original depth shim/oil slinger to
compensate for the difference in the depth variances.
Refer to the Depth Variance chart.
3 - 50 FRONT AXLE - 248FBIBR/BE
FRONT AXLE - 248FBI (Continued)

needed to preload the new bearings when the differ-
ential is installed.
(13) Rotate dial indicator out of the way on the
pilot stud.
(14) Remove differential case and dummy bearings
from the housing.
(15) Install the pinion gear in the housing. Install
the pinion yoke and establish the correct pinion
rotating torque.
(16) Install differential case and dummy bearings
D-343 in the housing (without shims), install bearing
caps and tighten bolts snug.
(17) Seat ring gear side dummy bearing (Fig. 13).
(18) Position the dial indicator plunger on a flat
surface between the ring gear bolt heads (Fig. 14).
(19) Push and hold differential case toward pinion
gear and zero the dial indicator (Fig. 17).
(20) Push and hold differential case to ring gear
side of the housing and record dial indicator reading
(Fig. 18).
(21) This is the shim thickness needed on the ring
gear side of the differential case for proper backlash.
(22) Subtract the backlash shim thickness from
the total preload shim thickness. The remainder is
the shim thickness required on the pinion side of the
housing.
(23) Rotate dial indicator out of the way on pilot
stud.
(24) Remove differential case and dummy bearings
from the housing.
(25) Install the selected side bearing shims onto
the differential case hubs.
(26) Install side bearings on differential case hubs
with Install C-4487-1 and Handle C-4171.
(27) Install bearing cups on differential.(28) Install Spreader W-129-B and some items
from Adapter Set 6987 on the housing and spread
open enough to receive differential case.
CAUTION: Do not spread housing over 0.50 mm
(0.020 in.). The housing can be damaged if over-
spread.
(29) Install differential case into the housing.
(30) Remove spreader from the housing.
Fig. 16 Differential Case To Ring Gear Side
1 - DIAL INDICATOR
2 - DIFFERENTIAL CASE TO RING GEAR SIDE
3 - DIFFERENTIAL HOUSING
Fig. 17 Differential Case To Pinion Gear Side
1 - DIAL INDICATOR FACE
2 - DIFFERENTIAL CASE TO PINION GEAR SIDE
3 - PINION GEAR
4 - DIFFERENTIAL HOUSING
5 - DIFFERENTIAL CASE
Fig. 18 Differential Case To Ring Gear Side
1 - DIAL INDICATOR
2 - DIFFERENTIAL CASE TO RING GEAR SIDE
3 - PINION GEAR
4 - DIFFERENTIAL HOUSING
5 - DIFFERENTIAL CASE
BR/BEFRONT AXLE - 248FBI 3 - 55
FRONT AXLE - 248FBI (Continued)

SPECIFICATIONS
FRONT AXLE - 248FBI
AXLE SPECIFICATIONS
DESCRIPTION SPECIFICATION
Axle Ratio 3.55, 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 1.7-4 N´m (15-35 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
3 - 58 FRONT AXLE - 248FBIBR/BE
FRONT AXLE - 248FBI (Continued)

(5) Position the yoke with the sockets in a vise
(Fig. 31).
(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. 32).
(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. 33).
(2) Install yoke on the pinion gear with Installer
C-3718 and Holder 6719 (Fig. 34).
CAUTION: Do not exceed the minimum tightening
torque when installing the pinion yoke retaining
nut. Damage to collapsible spacer or bearings may
result.
Fig. 30 Axle Shaft Outer UÐJoint
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. 31 Yoke Bearing Cap
1 - LARGE-DIAMETER SOCKET WRENCH
2 - VISE
3 - SMALL-DIAMETER SOCKET WRENCH
3 - 66 FRONT AXLE - 248FBIBR/BE
SINGLE CARDAN UNIVERSAL JOINTS (Continued)

(3) Install a new nut on the pinion gear. Tighten
the nut only enough to remove the shaft end play.
(4) Rotate the pinion shaft using an inch pound
torque wrench. Rotating torque should be equal to
the reading recorded during removal, plus an addi-
tional 0.56 N´m (5 in. lbs.) (Fig. 35).
(5) If the rotating torque is to low, use Holder 6719
to hold the pinion yoke (Fig. 36), and tighten the pin-
ion shaft nut in 6.8 N´m (5 ft. lbs.) until proper rotat-
ing torque is achieved.
(6) Align the installation reference marks and
attach the propeller shaft to the yoke.
(7) Check and add lubricant to axle, if necessary.
Refer to Lubricant Specifications in this section for
lubricant requirements.
(8) Install brake rotors and calipers.(9) Install wheel and tire assemblies.
(10) Lower the vehicle.
Fig. 32 Pinion
1 - YOKE HOLDER
2 - YOKE
3 - YOKE PULLER
Fig. 33 Pinion Seal Installation
1 - SPECIAL TOOL CÐ4171
2 - SPECIAL TOOL CÐ8108
Fig. 34 Install Pinion Yoke
1 - YOKE INSTALLER
2 - YOKE HOLDER
Fig. 35 Check Pinion Rotation
1 - PINION YOKE
2 - INCH POUND TORQUE WRENCH
BR/BEFRONT AXLE - 248FBI 3 - 67
PINION SEAL (Continued)