2001 DODGE RAM engine

(5) Position universal joint into pinion yoke for
Dana axles and tighten strap bolts to 29 N´m (22 ft.
lbs.).
(6) Position companion yoke onto the companion
flange for Corporate axles and tighten the bolts to
108 N´m (80 ft. lbs.).
(7) Lower the vehicle.
CENTER BEARING
DESCRIPTION
The two±piece propeller shaft uses a center bearing
to support the shafts. Two types of center bearings
are used. Type 1 is used with the 9 1/4 axle. Type 2
is used with the Dana axles (Fig. 18). Both types are
mounted in the same location.
OPERATION
The propeller shaft center bearing serves to divide
the required propeller shaft length into two smaller
shafts, which has several inherent advantages. Hav-
ing two short propeller shafts instead of one long
shaft decreases the chance of unwanted noise and
vibrations. The shorter shafts are easier to balance
and serve to increase ground clearance while main-
taining acceptable driveline angles.
REMOVAL
Two types of center bearings are used. The two
types are not interchangeable. Be sure to install the
same type as the vehicle was built with.
(1) Remove rear propeller shaft.
(2) Remove slip joint boot clamp and separate the
two half-shafts.(3) Use hammer and punch to tap slinger away
from shaft to provide room for bearing splitter.
(4) Position Bearing Splitter Tool 1130 between
slinger and shaft.
CAUTION: Do not damage shaft spline during
removal of center bearing.
(5) Set shaft in press and press bearing off the
shaft.
INSTALLATION
Two types of center bearings are used. The two
types are not interchangeable. Be sure to install the
same type as the vehicle was built with.
(1) Install new slinger on shaft and drive into posi-
tion with appropriate installer tool.
(2) Install new center bearing on shaft with Bear-
ing Installer Tool 6052. Drive on shaft with hammer
until bearing is seated.
(3) Clean shaft splines and apply a coat of multi±
purpose grease.
(4) Align master splines and slide front and rear
half-shafts together. Reposition slip yoke boot and
install new clamp.
(5) Install propeller shaft in vehicle.
CENTER BEARING ADJUSTMENT
Launch shudder is a vibration that occurs at first
acceleration from a stop. Shudder vibration usually
peaks at the engines highest torque output. Shudder
is a symptom associated with vehicles using a two-
piece propeller shaft. To decrease shudder, lower the
center bearing in 1/8 inch increments. Use shim
stock or fabricated plates. Plate stock must be used
Fig. 17 Rear Propeller ShaftÐCorporate Axles
1 - COMPANION FLANGE
2 - FLANGE YOKE
3 - REAR PROPELLER SHAFT
Fig. 18 Center Bearing
1 - SUPPORT BRACKET
2 - CENTER BEARING ASSEMBLY
3 - CENTER BEARING ASSEMBLY
4 - SUPPORT BRACKET
3 - 10 PROPELLER SHAFTBR/BE
PROPELLER SHAFT - REAR (Continued)

FRONT AXLE - 216FBI
TABLE OF CONTENTS
page page
FRONT AXLE - 216FBI
DESCRIPTION...........................12
OPERATION.............................12
DIAGNOSIS AND TESTING.................13
AXLE................................13
REMOVAL..............................16
INSTALLATION...........................17
ADJUSTMENTS..........................17
SPECIFICATIONS........................25
SPECIAL TOOLS.........................25
AXLE SHAFTS
REMOVAL..............................28
INSTALLATION...........................28
AXLE SHAFTS - INTERMEDIATE
REMOVAL..............................28
INSTALLATION...........................28
AXLE SHAFT SEALS
REMOVAL..............................29
INSTALLATION...........................29
AXLE VACUUM MOTOR
DESCRIPTION...........................29
OPERATION.............................30
DIAGNOSIS AND TESTING.................31VACUUM MOTOR.......................31
REMOVAL..............................33
DISASSEMBLY...........................33
ASSEMBLY.............................33
INSTALLATION...........................33
SINGLE CARDAN UNIVERSAL JOINTS
REMOVAL..............................33
INSTALLATION...........................34
PINION SEAL
REMOVAL..............................34
INSTALLATION...........................34
DIFFERENTIAL
REMOVAL..............................36
DISASSEMBLY...........................36
ASSEMBLY.............................37
INSTALLATION...........................37
DIFFERENTIAL CASE BEARINGS
REMOVAL..............................39
INSTALLATION...........................39
PINION GEAR/RING GEAR
REMOVAL..............................40
INSTALLATION...........................42
FRONT AXLE - 216FBI
DESCRIPTION
The housing for the 216 Front Beam-design Iron
(FBI) axles consists of an iron center casting with
tubes on each side. The tubes are pressed into and
welded to the differential housing.
The integral type housing, hypoid gear design has
the centerline of the pinion set below the centerline
of the ring gear.
The axle has a vent used to relieve internal pres-
sure caused by lubricant vaporization and internal
expansion.
The axles are equipped with semi-floating axle
shafts, meaning that loads are supported by the hub
bearings. The axle shafts are retained by nuts at the
hub bearings. The hub bearings are bolted to the
steering knuckle at the outboard end of the axle tube
yoke. The hub bearings are serviced as an assembly.
The axles are equipped with ABS brake sensors.
The sensors are attached to the knuckle assemblies
and the tone rings are pressed onto the axle shaft.
Use care when removing axle shafts as NOT to
damage the tone wheel or the sensor.The stamped steel cover provides a means for
inspection and servicing the differential.
The 216 axle have the assembly part number and
gear ratio listed on a tag. The tag is attached to the
housing cover by one of the cover bolts. Build date
identification codes are stamped on the cover side of
a axle tube.
The differential case is a one-piece design. The dif-
ferential pinion mate shaft is retained with a roll
pin. Differential bearing preload and ring gear back-
lash is adjusted by the use of shims. The shims are
located between the differential bearing cones and
case. Pinion bearing preload is set and maintained by
the use of a collapsible spacer.
The axle differential covers can be used for identi-
fication of the axle (Fig. 1). A tag is also attached to
the cover.
OPERATION
The axle receives power from the transfer case
through the front propeller shaft. The front propeller
shaft is connected to the pinion gear which rotates
the differential through the gear mesh with the ring
gear bolted to the differential case. The engine power
is transmitted to the axle shafts through the pinion
3 - 12 FRONT AXLE - 216FBIBR/BE

cle turns. A worn pinion mate shaft can also cause a
snapping or a knocking noise.
BEARING NOISE
The axle shaft, differential and pinion bearings can
all produce noise when worn or damaged. Bearing
noise can be either a whining, or a growling sound.
Pinion bearings have a constant-pitch noise. This
noise changes only with vehicle speed. Pinion bearing
noise will be higher pitched because it rotates at a
faster rate. Drive the vehicle and load the differen-
tial. If bearing noise occurs, the rear pinion bearing
is the source of the noise. If the bearing noise is
heard during a coast, the front pinion bearing is the
source.
Worn or damaged differential bearings usually pro-
duce a low pitch noise. Differential bearing noise is
similar to pinion bearing noise. The pitch of differen-
tial bearing noise is also constant and varies only
with vehicle speed.
Axle shaft bearings produce noise and vibration
when worn or damaged. The noise generally changes
when the bearings are loaded. Road test the vehicle.
Turn the vehicle sharply to the left and to the right.
This will load the bearings and change the noise
level. Where axle bearing damage is slight, the noise
is usually not noticeable at speeds above 30 mph.
LOW SPEED KNOCK
Low speed knock is generally caused by a worn
U-joint or by worn side-gear thrust washers. A worn
pinion shaft bore will also cause low speed knock.
VIBRATION
Vibration at the rear of the vehicle is usually
caused by:
²Damaged drive shaft.²Missing drive shaft balance weight(s).
²Worn or out of balance wheels.
²Loose wheel lug nuts.
²Worn U-joint(s).
²Loose/broken springs.
²Damaged axle shaft bearing(s).
²Loose pinion gear nut.
²Excessive pinion yoke run out.
²Bent axle shaft(s).
Check for loose or damaged front end components
or engine/transmission mounts. These components
can contribute to what appears to be a rear end
vibration. Do not overlook engine accessories, brack-
ets and drive belts.
All driveline components should be examined
before starting any repair.
(Refer to 22 - TIRES/WHEELS - DIAGNOSIS AND
TESTING)
DRIVELINE SNAP
A snap or clunk noise when the vehicle is shifted
into gear (or the clutch engaged) can be caused by:
²High engine idle speed.
²Transmission shift operation.
²Loose engine/transmission/transfer case mounts.
²Worn U-joints.
²Loose spring mounts.
²Loose pinion gear nut and yoke.
²Excessive ring gear backlash.
²Excessive side gear to case clearance.
The source of a snap or a clunk noise can be deter-
mined with the assistance of a helper. Raise the vehi-
cle on a hoist with the wheels free to rotate. Instruct
the helper to shift the transmission into gear. Listen
for the noise, a mechanics stethoscope is helpful in
isolating the source of a noise.
3 - 14 FRONT AXLE - 216FBIBR/BE
FRONT AXLE - 216FBI (Continued)

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. 27 Vacuum Control System
1 - CHECK VALVE
2 - CONTROL SWITCH ON TRANSFER CASE
3 - AIR VENT FILTER
4 - AXLE SHIFT MOTOR
5 - INDICATOR SWITCH
3 - 30 FRONT AXLE - 216FBIBR/BE
AXLE VACUUM MOTOR (Continued)

DIFFERENTIAL
REMOVAL
(1) Raise and support vehicle.
(2) Remove lubricant fill hole plug from the differ-
ential housing cover.
(3) Remove differential housing cover and drain
the lubricant from the housing.
(4) Clean the housing cavity with a flushing oil,
light engine oil or lint free cloth.Do not use water,
steam, kerosene or gasoline for cleaning.
(5) Remove hub bearings and axle shafts.
(6) Note the installation reference letters stamped
on the bearing caps and housing machined sealing
surface (Fig. 37).
(7) Remove the differential bearing caps.
(8) Position Spreader W-129-B with the tool dowel
pins seated in the locating holes (Fig. 38).
(9) Install the hold down clamps and tighten the
spreader turnbuckle finger-tight.
(10) Install Pilot Stud C-3288-B to the left side of
the differential housing and attach dial indicator to
the pilot stud. Load the indicator plunger against the
opposite side of the housing (Fig. 38) and zero the
dial indicator.
(11) Spread the housing enough to remove the case
from the housing. Measure the distance with the dial
indicator (Fig. 38).
CAUTION: Do not spread over 0.50 mm (0.020 in). If
the housing is over-spread it could be distorted or
damaged.
(12) Remove the dial indicator.(13) Pry the differential case loose from the hous-
ing. To prevent damage, pivot on housing with the
end of the pry bar against spreader (Fig. 39).
(14) Remove the case from housing.
(15) Remove and tag bearing cups to indicate their
original location.
DISASSEMBLY
(1) Remove roll-pin holding mate shaft in housing.
(2) Remove pinion gear mate shaft (Fig. 40).
Fig. 36 Pinion Shaft Nut
1 - PINION FLANGE
2 - HOLDING TOOL 6719
3 - AXLE HOUSING
Fig. 37 Bearing Cap Reference
1 - REFERENCE LETTERS
2 - REFERENCE LETTERS
Fig. 38 Spread Differential Housing
1 - HOUSING SPREADER W-129B
2 - DIAL INDICATOR C-3339
3 - DIFFERENTIAL
4 - AXLE HOUSING
5 - GUIDE PIN C-3288±B
3 - 36 FRONT AXLE - 216FBIBR/BE
PINION SEAL (Continued)

FRONT AXLE - 248FBI
TABLE OF CONTENTS
page page
FRONT AXLE - 248FBI
DESCRIPTION...........................45
OPERATION.............................45
DIAGNOSIS AND TESTING.................46
AXLE................................46
REMOVAL..............................50
INSTALLATION...........................50
ADJUSTMENTS..........................50
SPECIFICATIONS........................58
SPECIAL TOOLS.........................58
AXLE SHAFTS
REMOVAL..............................60
INSTALLATION...........................60
AXLE SHAFTS - INTERMEDIATE
REMOVAL..............................60
INSTALLATION...........................61
AXLE SHAFT SEALS
REMOVAL..............................61
INSTALLATION...........................61
AXLE VACUUM MOTOR
DESCRIPTION...........................62
OPERATION.............................62
DIAGNOSIS AND TESTING.................63VACUUM MOTOR.......................63
REMOVAL..............................65
DISASSEMBLY...........................65
ASSEMBLY.............................65
INSTALLATION...........................65
SINGLE CARDAN UNIVERSAL JOINTS
REMOVAL..............................65
INSTALLATION...........................66
PINION SEAL
REMOVAL..............................66
INSTALLATION...........................66
DIFFERENTIAL
REMOVAL..............................68
DISASSEMBLY...........................68
ASSEMBLY.............................69
INSTALLATION...........................69
DIFFERENTIAL CASE BEARINGS
REMOVAL..............................71
INSTALLATION...........................71
PINION GEAR/RING GEAR
REMOVAL..............................72
INSTALLATION...........................74
FRONT AXLE - 248FBI
DESCRIPTION
The housing for the 248 Front Beam-design Iron
(FBI) axle consists of an iron center casting with
tubes on each side. The tubes are pressed into and
welded to the differential housing.
The integral type housing, hypoid gear design has
the centerline of the pinion set below the centerline
of the ring gear.
The axle has a vent used to relieve internal pres-
sure caused by lubricant vaporization and internal
expansion.
The axles are equipped with semi-floating axle
shafts, meaning that loads are supported by the hub
bearings. The axle shafts are retained by nuts at the
hub bearings. The hub bearings are bolted to the
steering knuckle at the outboard end of the axle tube
yoke. The hub bearings are serviced as an assembly.
The axles are equipped with ABS brake sensors.
The sensors are attached to the knuckle assemblies
and the tone rings are pressed onto the axle shaft.
Use care when removing axle shafts as NOT to
damage the tone wheel or the sensor.The stamped steel cover provides a means for
inspection and servicing the differential.
The 248 FBI axle have the assembly part number
and gear ratio listed on a tag. The tag is attached to
the housing cover by one of the cover bolts. Build
date identification codes are stamped on the cover
side of a axle tube.
The differential case is a one-piece design. The dif-
ferential pinion mate shaft is retained with a roll
pin. Differential bearing preload and ring gear back-
lash is adjusted by the use of shims. The shims are
located between the differential bearing cones and
case. Pinion bearing preload is set and maintained by
the use of a collapsible spacer.
The axle differential covers can be used for identi-
fication of the axle (Fig. 1). A tag is also attached to
the cover.
OPERATION
The axle receives power from the transfer case
through the front propeller shaft. The front propeller
shaft is connected to the pinion gear which rotates
the differential through the gear mesh with the ring
gear bolted to the differential case. The engine power
is transmitted to the axle shafts through the pinion
BR/BEFRONT AXLE - 248FBI 3 - 45

cle turns. A worn pinion mate shaft can also cause a
snapping or a knocking noise.
BEARING NOISE
The axle shaft, differential and pinion bearings can
all produce noise when worn or damaged. Bearing
noise can be either a whining, or a growling sound.
Pinion bearings have a constant-pitch noise. This
noise changes only with vehicle speed. Pinion bearing
noise will be higher pitched because it rotates at a
faster rate. Drive the vehicle and load the differen-
tial. If bearing noise occurs, the rear pinion bearing
is the source of the noise. If the bearing noise is
heard during a coast, the front pinion bearing is the
source.
Worn or damaged differential bearings usually pro-
duce a low pitch noise. Differential bearing noise is
similar to pinion bearing noise. The pitch of differen-
tial bearing noise is also constant and varies only
with vehicle speed.
Axle shaft bearings produce noise and vibration
when worn or damaged. The noise generally changes
when the bearings are loaded. Road test the vehicle.
Turn the vehicle sharply to the left and to the right.
This will load the bearings and change the noise
level. Where axle bearing damage is slight, the noise
is usually not noticeable at speeds above 30 mph.
LOW SPEED KNOCK
Low speed knock is generally caused by a worn
U-joint or by worn side-gear thrust washers. A worn
pinion shaft bore will also cause low speed knock.
VIBRATION
Vibration at the rear of the vehicle is usually
caused by:
²Damaged drive shaft.²Missing drive shaft balance weight(s).
²Worn or out of balance wheels.
²Loose wheel lug nuts.
²Worn U-joint(s).
²Loose/broken springs.
²Damaged axle shaft bearing(s).
²Loose pinion gear nut.
²Excessive pinion yoke run out.
²Bent axle shaft(s).
Check for loose or damaged front end components
or engine/transmission mounts. These components
can contribute to what appears to be a rear end
vibration. Do not overlook engine accessories, brack-
ets and drive belts.
All driveline components should be examined
before starting any repair.
(Refer to 22 - TIRES/WHEELS - DIAGNOSIS AND
TESTING)
DRIVELINE SNAP
A snap or clunk noise when the vehicle is shifted
into gear (or the clutch engaged) can be caused by:
²High engine idle speed.
²Transmission shift operation.
²Loose engine/transmission/transfer case mounts.
²Worn U-joints.
²Loose spring mounts.
²Loose pinion gear nut and yoke.
²Excessive ring gear backlash.
²Excessive side gear to case clearance.
The source of a snap or a clunk noise can be deter-
mined with the assistance of a helper. Raise the vehi-
cle on a hoist with the wheels free to rotate. Instruct
the helper to shift the transmission into gear. Listen
for the noise, a mechanics stethoscope is helpful in
isolating the source of a noise.
BR/BEFRONT AXLE - 248FBI 3 - 47
FRONT AXLE - 248FBI (Continued)

AXLE VACUUM MOTOR
DESCRIPTION
The disconnect axle control system consists of:
²Shift motor.
²Indicator switch.
²Vacuum switch.
²Vacuum harness (Fig. 27).
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. Whenthis 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. 26 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. 27 Vacuum Control System
1 - CHECK VALVE
2 - CONTROL SWITCH ON TRANSFER CASE
3 - AIR VENT FILTER
4 - AXLE SHIFT MOTOR
5 - INDICATOR SWITCH
3 - 62 FRONT AXLE - 248FBIBR/BE
AXLE SHAFT SEALS (Continued)