rear diff DODGE RAM 2001 Service Workshop Manual

(2) Remove factory installed shims from differen-
tial case.
(3) Install ring gear on differential case and
tighten bolts to specification.
(4) Install dummy side bearings D-343 on differen-
tial case.
(5) Install differential case in the housing.
(6) Install the marked bearing caps in their correct
positions and snug the bolts (Fig. 11).(7) Using a dead-blow hammer, seat the differen-
tial dummy bearings to each side of the housing (Fig.
12) and (Fig. 13).
(8) Thread Pilot Stud C-3288-B into rear cover bolt
hole below ring gear (Fig. 14).
(9) Attach the Dial Indicator C-3339 to pilot stud.
Position the dial indicator plunger on a flat surface
between the ring gear bolt heads (Fig. 14).
(10) Push and hold differential case to pinion gear
side of the housing and zero dial indicator (Fig. 15).
(11) Push and hold differential case to ring gear
side of the housing and record the dial indicator
reading (Fig. 16).
Fig. 10 Adjustment Shim Loactions
1 - PINION GEAR DEPTH SHIM/OIL BAFFLE
2 - DIFFERENTIAL BEARING SHIM
Fig. 11 Bearing Cap Bolts
1 - BEARING CAP
2 - DIFFERENTIAL HOUSING
3 - DIFFERENTIAL CASE
Fig. 12 Seat Pinion Gear Side Dummy Bearing
1 - DEAD-BLOW HAMMER
2 - DIFFERENTIAL HOUSING
3 - DIFFERENTIAL CASE
Fig. 13 Seat Ring Gear Side Differential Dummy
Bearing
1 - DIFFERENTIAL HOUSING
2 - DEAD-BLOW HAMMER
3 - DIFFERENTIAL CASE
BR/BEREAR AXLE - 248RBI 3 - 117
REAR AXLE - 248RBI (Continued)

(12) Add 0.38 mm (0.015 in.) to the zero end play
total. This total represents the thickness of shims
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).
Fig. 14 Differential Side Play Measurement
1 - DIFFERENTIAL CASE
2 - DIFFERENTIAL HOUSING
3 - PILOT STUD
4 - DIAL INDICATOR
Fig. 15 Dial Indicator Location
1 - DIFFERENTIAL CASE TO PINION GEAR SIDE
2 - PILOT STUD
3 - DIAL INDICATOR ARM
4 - DIAL INDICATOR FACE
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
3 - 118 REAR AXLE - 248RBIBR/BE
REAR AXLE - 248RBI (Continued)

(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.
(31) Rotate the differential case several times to
seat the side bearings.
(32) Position the indicator plunger against a ring
gear tooth (Fig. 19).
(33) Push and hold ring gear upward while not
allowing the pinion gear to rotate.
(34) Zero dial indicator face to pointer.
(35) Push and hold ring gear downward while not
allowing the pinion gear to rotate. Dial indicator
reading should be between 0.12 mm (0.005 in.) and
0.20 mm (0.008 in.). If backlash is not within specifi-
cations transfer the necessary amount of shim thick-
ness from one side of the housing to the other (Fig.
20).
(36) Verify differential case and ring gear runout
by measuring ring to pinion gear backlash at eight
locations around the ring gear. Readings should not
vary more than 0.05 mm (0.002 in.). If readings vary
more than specified, the ring gear or the differential
case is defective.
After the proper backlash is achieved, perform
Gear Contact Pattern Analysis procedure.
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
Fig. 19 Ring Gear Backlash Measurement
1 - DIAL INDICATOR
BR/BEREAR AXLE - 248RBI 3 - 119
REAR AXLE - 248RBI (Continued)

GEAR CONTACT PATTERN
The ring and pinion gear contact patterns will
show if the pinion depth is correct. It will also show
if the ring gear backlash has been adjusted correctly.
The backlash can be adjusted within specifications to
achieve desired tooth contact patterns.
(1) Apply a thin coat of hydrated ferric oxide or
equivalent to the drive and coast side of the ring gear
teeth.
(2) Wrap, twist and hold a shop towel around the
pinion yoke to increase the turning resistance of the
pinion. This will provide a more distinct contact pat-
tern.
(3) With a boxed end wrench on the ring gear bolt,
rotate the differential case one complete revolution in
both directions while a load is being applied from
shop towel.
The areas on the ring gear teeth with the greatest
degree of contact against the pinion teeth will squee-
gee the compound to the areas with the least amount
of contact. Note and compare patterns on the ring
gear teeth to Gear Tooth Contact Patterns chart (Fig.
21)and adjust pinion depth and gear backlash as nec-
essary.
Fig. 20 Backlash Shim
3 - 120 REAR AXLE - 248RBIBR/BE
REAR AXLE - 248RBI (Continued)

SPECIFICATIONS
REAR AXLE - 248RBI
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 127.0 mm (5.000 in.)
Pinion Bearing Preload - Original Bearings 1-2 N´m (10-20 in. lbs.)
Pinion Bearing Preload - New Bearings 2.3-5.1 N´m (20-45 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 Bolt 176 130 -
Pinion Nut 292-447 215-330 -
Axle Shaft Bolts 122-136 90-100 -
Hub Bearing Nut 163-190 120-140 -
SPECIAL TOOLS
REAR AXLE - 248RBI
Puller 6790
Wrench DD-1241-JD
Installer 5064
Installer D-111
3 - 122 REAR AXLE - 248RBIBR/BE
REAR AXLE - 248RBI (Continued)

(2) Install new pinion seal with an aproppriate
installer (Fig. 23).
NOTE: The seal is correctly installed when the seal
flange contacts the face of the differential housing
flange.
(3) Position the pinion yoke on the end of the shaft
with the reference marks aligned.
(4) Seat yoke on pinion shaft with Installer C-3718
and Yoke Holder 6719.
(5) Remove the tools and install the pinion yoke
washer and nut.
CAUTION: Do not exceed the minimum tightening
torque when installing the pinion yoke retaining nut
at this point. Damage to collapsible spacer, if
equipped, or bearings may result.(6) Hold pinion yoke with Yoke Holder 6719 and
tighten shaft nut to 291.5 N´m (215 ft. lbs.) (Fig. 24).
Rotate pinion shaft several revolutions to ensure the
bearing rollers are seated.
(7) Rotate the pinion shaft using a (in. lbs.) torque
wrench. Rotating resistance torque should be equal
to the reading recorded during removal, plus an addi-
tional 0.56 N´m (5 in. lbs.) (Fig. 25).
CAUTION: Never loosen pinion gear nut to decrease
pinion gear bearing rotating torque and never
exceed specified preload torque. If preload torque
is exceeded a new pinion nut and collapsible
spacer, if equipped, must be installed. The torque
sequence will then have to be repeated.
(8) If the rotating torque is low, use Yoke Holder
6719 to hold the pinion yoke (Fig. 24) and tighten the
pinion shaft nut in 6.8 N´m (5 ft. lbs.) increments
until proper rotating torque is achieved.
NOTE: The bearing rotating torque should be con-
stant during a complete revolution of the pinion. If
the rotating torque varies, this indicates a binding
condition.
(9) Install the propeller shaft with the installation
reference marks aligned.
(10) Tighten the universal joint yoke clamp screws
to 19 N´m (14 ft. lbs.).
Fig. 22 Yoke Removal
1 - PINION YOKE
2 - REMOVER C452
Fig. 23 Pinion Seal Installation
1 - SPECIAL TOOL CÐ4171
2 - SPECIAL TOOL CÐ8108
Fig. 24 Tightening Pinion Shaft Nut
1 - DIFFERENTIAL HOUSING
2 - YOKE HOLDER
3 - TORQUE WRENCH
3 - 126 REAR AXLE - 248RBIBR/BE
PINION SEAL (Continued)

(11) Install the brake drums.
(12) Add gear lubricant to the differential housing,
if necessary. Refer to the Lubricant Specifications for
gear lubricant requirements.
(13) Install wheel and tire assemblies and lower
the vehicle.
DIFFERENTIAL
REMOVAL
(1) Raise and support the vehicle.
(2) Remove the lubricant fill hole plug from the
differential 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 axle shafts.
(6) Note the orientation of the installation refer-
ence letters stamped on the bearing caps and hous-
ing machined sealing surface (Fig. 26).
(7) Remove the differential bearing caps.
(8) Position Spreader W-129-B with the tool dowel
pins seated in the locating holes (Fig. 27).
(9) Install the hold down clamps and tighten the
tool turnbuckle finger-tight.
(10) Install a Pilot Stud C-3288-B at the left side
of the differential housing. Attach dial indicator tohousing pilot stud. Load the indicator plunger
against the opposite side of the housing (Fig. 27) and
zero the indicator.
(11) Spread the housing enough to remove the case
from the housing. Measure the distance with the dial
indicator (Fig. 27).
CAUTION: Do not spread over 0.50 mm (0.020 in). If
the housing is over-spread, it could be distorted or
damaged.
Fig. 25 Check Pinion Rotation Torque
1 - PINION YOKE
2 - INCH POUND TORQUE WRENCH
Fig. 26 Bearing Cap Identification
1 - REFERENCE LETTERS
2 - REFERENCE LETTERS
Fig. 27 Spread Differential Housing
1 - SPREADER
2 - DIAL INDICATOR
3 - DIFFERENTIAL
4 - DIFFERENTIAL HOUSING
5 - PILOT STUD
BR/BEREAR AXLE - 248RBI 3 - 127
PINION SEAL (Continued)

(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. 28).
(14) Remove the case from housing. Tag bearing
cups to indicate their location.
DISASSEMBLY
(1) Remove roll-pin holding mate shaft in housing.
(2) Remove pinion gear mate shaft (Fig. 29).
(3) Rotate the differential side gears and remove
the pinion mate gears and thrust washers (Fig. 30).
(4) Remove the differential side gears and thrust
washers.
ASSEMBLY
(1) Install the differential side gears and thrust
washers.
(2) Install the pinion mate gears and thrust wash-
ers.
(3) Install the pinion gear mate shaft.
(4) Align the hole in the pinion gear mate shaft
with the hole in the differential case.
(5) Install and seat the pinion mate shaft roll-pin
in the differential case and mate shaft with a punch
and hammer (Fig. 31). Peen the edge of the roll-pin
hole in the differential case slightly in two places,
180É apart.(6) Lubricate all differential components with
hypoid gear lubricant.
Fig. 28 Differential Removal
1 - DIFFERENTIAL
2-PRYBAR
Fig. 29 Pinion Mate Shaft
1 - PINION MATE GEAR
2 - PINION MATE SHAFT
3 - SIDE GEAR
4 - DRIFT
Fig. 30 Pinion Mate/Side Gear
1 - THRUST WASHER
2 - SIDE GEAR
3 - PINION MATE GEAR
3 - 128 REAR AXLE - 248RBIBR/BE
DIFFERENTIAL (Continued)

INSTALLATION
NOTE: If replacement differential bearings or differ-
ential case are being installed, differential side
bearing shim requirements may change. Refer to
Adjustments (Differential Bearing Preload and Gear
Backlash) procedures to determine proper shim
selection.
(1) Position Spreader W-129-B with the tool dowel
pins seated in the locating holes. Install the hold
down clamps and tighten the tool turnbuckle finger-
tight.
(2) Install a Pilot Stud C-3288-B at 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 and zero the dial indica-
tor.
(3) Spread the housing enough to install the case
in the housing. Measure the distance with the dial
indicator.
CAUTION: Do not spread over 0.50 mm (0.020 in). If
the housing is over-spread, it could be distorted or
damaged.
(4) Remove the dial indicator.(5) Install differential into the housing. Tap the
differential case with a rawhide/rubber hammer to
ensure the bearings are seated in housing (Fig. 32).
(6) Remove the spreader.
(7) Install bearing caps in their original locations
(Fig. 33) and tighten bearing cap bolts to 109 N´m
(80 ft. lbs.).
(8) Install axle shafts.
(9) Install the hub bearings.
Fig. 31 Pinion Mate Shaft Roll-Pin
1 - PUNCH
2 - PINION MATE SHAFT
3 - MATE SHAFT LOCKPIN
Fig. 32 Differential Case
1 - RAWHIDE HAMMER
Fig. 33 Bearing Cap Reference
1 - REFERENCE LETTERS
2 - REFERENCE LETTERS
BR/BEREAR AXLE - 248RBI 3 - 129
DIFFERENTIAL (Continued)

(10) Apply a bead of Mopar Silicone Rubber Seal-
ant or equivalent to the housing cover (Fig. 34).
Install the housing cover within 5 minutes
after applying the sealant.
(11) Install the cover and any identification tag.
Tighten the cover bolts in a criss-cross pattern to 47
N´m (35 ft. lbs.).
(12) Refill the differential with Mopar Hypoid
Gear Lubricant or equivalent to bottom of the fill
plug hole. Refer to the Lubricant Specifications for
correct quantity and type.
(13) Install the fill hole plug and tighten to 34 N´m
(25 ft. lbs.).
(14) Remove support and lower vehicle.
DIFFERENTIAL - TRAC-LOK
DIAGNOSIS AND TESTING - TRAC-LOKY
The most common problem is a chatter noise when
turning corners. Before removing a Trac-lokyunit
for repair, drain, flush and refill the axle with the
specified lubricant. A container of Mopar Trac-loky
Lubricant (friction modifier) should be added after
repair service or during a lubricant change.
After changing the lubricant, drive the vehicle and
make 10 to 12 slow, figure-eight turns. This maneu-
ver will pump lubricant through the clutches. Thiswill correct the condition in most instances. If the
chatter persists, clutch damage could have occurred.
DIFFERENTIAL TEST
The differential can be tested without removing the
differential case by measuring rotating torque. Make
sure brakes are not dragging during this measure-
ment.
(1) Place blocks in front and rear of both front
wheels.
(2) Raise one rear wheel until it is completely off
the ground.
(3) Engine off, transmission in neutral, and park-
ing brake off.
(4) Remove wheel and bolt Special Tool 6790 or
equivalent tool to studs.
(5) Use torque wrench on special tool to rotate
wheel and read rotating torque (Fig. 35).
(6) If rotating torque is less than 22 N´m (30 ft.
lbs.) or more than 271 N´m (200 ft. lbs.) on either
wheel the unit should be serviced.
DISASSEMBLY
(1) Clamp side gear Holding Fixture 6965 in a vise
and position the differential case on the Holding Fix-
ture (Fig. 36).
(2) Remove ring gear if the ring gear is to be
replaced. The Trac-lokydifferential can be serviced
with the ring gear installed.
(3) Remove pinion shaft roll pin.
(4) Remove pinion shaft with a drift and hammer
(Fig. 37).
(5) Install and lubricate Step Plate C-6960-3 (Fig.
38).
Fig. 34 Differential Cover
1 - SEALANT SURFACE
2 - SEALANT
3 - SEALANT THICKNESS
Fig. 35 Trac-lokYTest -Typical
1 - SPECIAL TOOL 6790 WITH BOLT IN CENTER HOLE
2 - TORQUE WRENCH
3 - 130 REAR AXLE - 248RBIBR/BE
DIFFERENTIAL (Continued)