1999 DODGE RAM Service Repair Manual

Installation
To install, reverse removal procedure using NEW "U" joint
straps and bolts. Ensure all reference marks are aligned. Tighten
bolts to specification. See TORQUE SPECIFICATIONS table.
PINION FLANGE & OIL SEAL
Removal
1) Raise and support vehicle. Reference mark drive shaft and
pinion flange on differential for reassembly. Remove bolts and "U"
joint straps at pinion flange on differential. Disconnect drive shaft
from differential, and support it aside.
2) Using INCH-lb. torque wrench, measure amount of force
required to rotate pinion. This is pinion bearing preload. Record
pinion bearing preload for reassembly reference.
3) Remove pinion nut and washer from pinion. Scribe reference
mark on pinion flange and pinion for reassembly. Using Holder (C-3281)\
and appropriate flange remover, remove pinion flange from pinion.
Remove oil seal from axle housing.
Installation
1) Ensure oil seal surface in axle housing is clean. Coat lip
of oil seal with gear lube. Using appropriate oil seal installer and
handle, install oil seal.
2) Install pinion flange on pinion with reference mark
aligned. Press pinion flange onto pinion. Install washer and pinion
nut. Tighten pinion nut while rotating pinion, ensuring bearings are
properly seated. Tighten nut until preload measured before disassembly
is achieved. DO NOT exceed maximum torque specification. See TORQUE
SPECIFICATIONS table.
3) To install remaining components, reverse removal procedure
using NEW "U" joint straps and bolts. Ensure all reference marks are
aligned. Tighten bolts to specification. See TORQUE SPECIFICATIONS
table. Check lubricant level and add if necessary.
AXLE HOUSING ASSEMBLY
NOTE: Removing axle housing assembly is not necessary unless axle
housing is damaged. Differential carrier and components can
be serviced by removing differential assembly from axle
housing.
Removal
1) Raise and support vehicle. Remove front wheels. Reference
mark drive shaft to pinion flange for reassembly. Remove bolts and "U"
joint straps at pinion flange. Remove drive shaft, and support aside.
Remove brake calipers, and support aside with wire. DO NOT allow
calipers to hang from brake hoses.
2) Disconnect ABS sensor harness connectors (if equipped).
Disconnect drag link and tie rod from steering knuckles. Disconnect
shock absorber from axle housing. Disconnect stabilizer bar links at
spring brackets.
3) Disconnect electrical connector and vacuum hoses at vacuum
shift motor. Support axle housing assembly with floor jack. Remove
bolts from upper and lower suspension arms. Lower axle housing
assembly from vehicle and remove.
Installation
To install, reverse removal procedure. Ensure reference marks
on drive shaft and pinion flange align. Tighten suspension arms with
vehicle at normal operating height. Tighten bolt/nuts to
specification. See TORQUE SPECIFICATIONS table. Check axle fluid level

and fill if necessary.
STEERING KNUCKLES
Removal & Installation
1) Raise and support vehicle. Remove hub bearing and axle
shaft. Remove tie rod or drag link end from steering knuckle arm.
Remove ABS sensor harness and bracket from steering knuckle.
2) Remove cotter pin from upper ball stud nut. Remove upper
and lower ball stud nuts. Using a brass hammer, strike steering
knuckle to remove knuckle from axle tube yokes.
3) To install, reverse removal procedure. On 216 FBI axles,
tighten lower and upper ball stud nuts to specification. See TORQUE
SPECIFICATIONS table.
4) On 248 FBI axles, tighten lower ball stud nut to
specification. DO NOT install cotter pin at this time. Install and
tighten upper ball stud nut to specification. Retorque lower ball stud
nut to specification. See TORQUE SPECIFICATIONS table.
AXLE SHIFT MOTOR
Removal & Installation
1) Disconnect vacuum and wiring connector from shift housing.
Remove indicator switch, shift motor housing cover, gasket and shield
from housing.
2) To install, reverse removal procedure. Ensure shift fork
is correctly guided into shift collar groove. Tighten mounting bolts
to 96 INCH lbs. (11 N.m). Add 5 ounces (148 ml) of GL-5 gear lubrica\
nt
to shift motor housing through indicator switch mounting hole.
DIFFERENTIAL ASSEMBLY
NOTE: Differential assembly consists of differential case and
components mounted in axle housing. For differential assembly
servicing, see DIFFERENTIAL ASSEMBLY under OVERHAUL.
OVERHAUL
DIFFERENTIAL ASSEMBLY
Disassembly
1) Remove axle shafts from differential. See AXLE SHAFT & HUB
BEARING under REMOVAL & INSTALLATION.
2) Note identification marks on bearing caps and axle housing
for reassembly reference. Bearing caps must be installed in original
location. If marks are not present, place marks on bearing caps and
axle housing.
3) Remove bolts and bearing caps. Place Axle Housing Spreader
(W-129-B) on axle housing so dowel pins engage with locating holes.
See Fig. 1 . Install hold-down clamps. Finger tighten turnbuckle on
axle housing spreader.
4) Install pilot stud and dial indicator on axle housing.
Position dial indicator so stem is resting against opposite side of
axle housing, with pressure on stem.
CAUTION: DO NOT spread axle housing more than .020" (.50 mm), or axle
housing may be damaged.
5) Adjust dial indicator to zero. Tighten turnbuckle enough
to spread axle housing for differential case removal while noting
reading on dial indicator. Dial indicator reading should not exceed .
020" (.50 mm).

Fig. 1: Installing Axle Housing Spreader
Courtesy of Chrysler Corp.
6) Remove dial indicator. Pry differential case from axle
housing. If reusing bearing races for differential bearings, mark
bearing race location for reassembly reference. Bearing races must be
installed with original differential bearing.
7) If removing ring gear, place differential case in soft-jaw
vise. Remove and discard ring gear bolts. Using soft-face hammer, tap
ring gear from differential case.
8) Remove pinion nut and washer from pinion. Scribe reference
mark on pinion flange and pinion if components are to be reused.
9) Using Holder (C-3281) and appropriate flange remover,
remove pinion flange from pinion. Remove oil seal from axle housing.
10) Remove slinger (if equipped), pinion bearing and preload\
shim(s). Note thickness of preload shims for reassembly reference in
case shims become misplaced.
11) Remove pinion and bearing from axle housing. Using
appropriate remover, remove front (outer) pinion bearing race from
axle housing. Remove rear (inner) pinion bearing race from axle
housing using remover. Remove pinion bearing depth shims from axle
housing. Measure and record shim thickness for reassembly reference.
12) Remove rear (inner) bearing from pinion, using
appropriate puller. Remove differential bearings from differential
case. Remove preload shims from differential case. Identify preload
shim location. Record preload shim thickness for reassembly reference.
13) Clamp differential case in soft-jaw vise. Remove roll pin
from differential case. Tap pinion shaft from differential case.

Remove pinion gears, pinion gear thrust washers, side gears and side
gear thrust washers from differential case.
Cleaning & Inspection
1) Clean components with solvent, and dry with compressed
air. Inspect components for wear. Inspect bearings and bearing races
for wear and pitting. Replace bearings and bearing races as a set.
Inspect ring gear and pinion teeth for wear and chipping. Replace ring
gear and pinion gear as matched set.
2) Check differential case for cracks or scoring of side
gears, thrust washers and pinion thrust faces. Check fit of side gears
to differential case and axle shaft splines. Examine shaft of pinion
shaft for scoring or excessive wear.
NOTE: Lubricate all bearings, bearing races, gears and thrust
washers with gear lube during reassembly.
Reassembly & Adjustments
1) Place differential case in soft-jaw vise. Install side
gears, side gear thrust washers, pinion gears and pinion gear thrust
washers in differential case.
2) Rotate side gears until holes in pinion gears and thrust
washers align with holes in differential case. Install pinion shaft.
Install roll pin in differential case. Stake edge of differential case
in 2 areas to retain roll pin in place. Remove differential case from
vise.
NOTE: Initial differential bearing preload must be performed to
determine thickness of preload shims in order to obtain zero
end play of differential case. Procedure must be performed
before installing pinion in axle housing.
3) Install ring gear on differential case. Use NEW ring gear
bolts. DO NOT reuse bolts. Tighten bolts evenly in alternating pattern
to specification. See TORQUE SPECIFICATIONS table. Proceed to INITIAL
DIFFERENTIAL BEARING PRELOAD.
Initial Differential Bearing Preload
1) Install dummy bearings on each side of differential case
where differential bearing fits. Use Dummy Bearing (D-345) for 216 FBI\
axle or (D-343) for 248 FBI axle.
2) Install differential case in axle housing. Install bearing
caps on axle housing. Ensure bearing caps are installed in original
location. Install bearing cap bolts.
3) Mount dial indicator on axle housing with stem against
back of ring gear. See Fig. 2. Pry between bearing cap and
differential case. Pry differential case to right as far as possible.
Zero dial indicator.
4) Pry differential case to the left as far as possible. Note
dial indicator reading. This reading is referred to as the
"differential case zero end play". Record differential case zero end
play reading.
5) Differential case zero end play measurement indicates
thickness of preload shims required to eliminate clearance between
differential bearings and bearing races.
6) Total thickness of preload shims will be determined during
ring gear backlash adjustment. Remove dial indicator, bearing caps and
differential case from axle housing. Proceed to PINION DEPTH
procedure.

Fig. 2: Measuring Differential Case End Play
Courtesy of Chrysler Corp.
Pinion Depth
1) Ring gear and pinion are a matched set. A gear matching
number is stamped on pinion face. This number must be same as number
on ring gear. A pinion depth variance marking is etched on pinion
face. See Fig. 3.
2) Etched marking (in thousandths of an inch) indicates
deviation from standard pinion depth setting. Standard pinion depth
setting is distance from center line of axle shaft to rear pinion
bearing shoulder area. See Fig. 3. Standard pinion depth setting
varies with axle model. See STANDARD PINION DEPTH SETTING table.
STANDARD PINION DEPTH SETTING









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Application In. (mm)\
216 FBI ............................................. 4.312 (109.52)\

248 FBI ............................................. 5.000 (127.00)\









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Fig. 3: Identifying Pinion Markings & Pinion Depth Measurement
Courtesy of Chrysler Corp.
3) If original pinion, ring gear and axle housing are being
used and pinion depth shims are being replaced, determine thickness of

original pinion depth shims. Replace shims with NEW shims of same
thickness.
4) If only pinion and ring gear are being replaced and
original axle housing is used, note pinion depth variance marking on
old pinion and replacement pinion.
5) Using etched markings and pinion depth shim adjustment
chart, determine amount to be added or subtracted from thickness of
original pinion depth shims. See Fig. 4. For example, if etched
marking is +4 on original pinion and -4 on replacement pinion,
thickness of pinion depth shims should be increased by .008" (.20 mm).\
NOTE: When using pinion depth shim adjustment chart, if result is a
negative (-) reading, subtract this amount from thickness of
pinion depth shim pack to obtain thickness of correct shim.
If result is positive (+), add this amount to thickness of
pinion depth shim pack to obtain thickness of correct shim.
If result is zero, this will be nominal standard pinion depth
setting and no shims are required. When using pinion depth
shim adjustment chart, thickness of original pinion depth
shim pack must be accurately determined. If original pinion
depth shim pack dimension cannot be accurately determined,
pinion depth gauge set must be used to properly determine
pinion depth setting. Pinion depth gauge set must also be
used if using replacement axle housing. Proceed to
DETERMINING PINION DEPTH USING PINION DEPTH GAUGE SET.
NOTE: If slinger is used, slinger thickness must also be included
in pinion depth shim pack.
Fig. 4: Pinion Depth Shim Adjustment Chart
Courtesy of Chrysler Corp.
Determining Pinion Depth Using Pinion Depth Gauge Set
1) Use Pinion Depth Gauge Set for all axle models. Place
master pinion block in pinion bore of axle housing. See Fig. 5.
Install discs on arbor. Install arbor in axle housing, with discs
positioned in differential bearing bores. See Fig. 5.
2) Install pinion height block on top of master pinion block,
against arbor. Place gauge block with dial indicator on lowest step of

pinion height block. Zero dial indicator with gauge block flat on
pinion height block.
3) Move gauge block so dial indicator stem contacts arbor.
Move gauge block back and forth (perpendicular to arbor) to get
highest reading. This reading is thickness of required pinion depth
shim pack.
4) To select correct shim, note etched markings on end of
pinion face. Etched marking (in thousandths of an inch) indicates
deviation from standard dimension.
5) When etched marking is negative (-), add this amount to
pinion depth shim pack to obtain correct shim thickness. When etched
marking is positive (+), subtract this amount from pinion depth shim
pack to obtain correct shim thickness. If etched marking is zero, no
change is required in pinion depth shim pack thickness.
6) Measure pinion depth shims separately using micrometer. If
slinger is used, slinger thickness must also be included in pinion
depth shim pack. Remove pinion depth gauge set components from axle
housing.
7) Place pinion depth shim pack in axle housing bore for rear
(inner) bearing race. Using appropriate bearing race installer, drive
rear (inner) bearing race into axle housing. Ensure bearing race is
fully seated.
8) Using bearing race installer, drive front (outer) bearing\
race into axle housing. Ensure bearing race is fully seated. Proceed
to PINION BEARING PRELOAD.
Fig. 5: Checking Pinion Depth
Courtesy of Chrysler Corp.
Pinion Bearing Preload
1) Install slinger on pinion (if equipped). Press rear