1998 DODGE RAM 1500 Rear differential

GROUP TAB LOCATOR
Introduction
0Lubrication & Maintenance
2Suspension
3Differential & Driveline
5Brakes
6Clutch
7Cooling
8AAudio/Video
8BChime/Buzzer
8EElectronic Control Modules
8FEngine Systems
8GHeated Systems
8HHorn
8IIgnition Control
8JInstrument Cluster
8LLamps
8MMessage Systems
8NPower Systems
8ORestraints
8PSpeed Control
8QVehicle Theft Security
8RWipers/Washers
8TNavigation/Telecommunication
8WWiring
9Engine
11Exhaust System
13Frame & Bumpers
14Fuel System
19Steering
21Transmission and Transfer Case
22Tires/Wheels
23Body
24Heating & Air Conditioning
25Emissions Control
Component and System Index
Service Manual Comment Forms (Rear of Manual)

tic and soften solder. The increased temperature can
result in engine detonation. In addition, 100 percent
ethylene-glycol freezes at -22ÉC (-8ÉF).
50/50 Ethylene-Glycol and Water-Is the recom-
mended mixture, it provides protection against freez-
ing to -37ÉC (-34ÉF). The antifreeze concentration
must alwaysbe a minimum of 44 percent, year-
round in all climates. If percentage is lower, engine
parts may be eroded by cavitation. Maximum protec-
tion against freezing is provided with a 68 percent
antifreeze concentration, which prevents freezing
down to -67.7ÉC (-90ÉF). A higher percentage will
freeze at a warmer temperature. Also, a higher per-
centage of antifreeze can cause the engine to over-
heat because specific heat of antifreeze is lower than
that of water.
CAUTION: Richer antifreeze mixtures cannot be
measured with normal field equipment and can
cause problems associated with 100 percent ethyl-
ene-glycol.
COOLANT SELECTION AND ADDITIVES
NOTE: Refer to the vehicle's coolant bottle to iden-
tify HOAT or Non-HOAT coolant. Non-HOAT coolant
is green in color.
The use of aluminum cylinder blocks, cylinder
heads and water pumps requires special corrosion
protection. Only MopartAntifreeze/Coolant, 5
Year/100,000 Mile Formula (glycol base coolant with
corrosion inhibitors called HOAT, for Hybrid Organic
Additive Technology) is recommended. This coolant
offers the best engine cooling without corrosion when
mixed with 50% distilled water to obtain to obtain a
freeze point of -37ÉC (-35ÉF). If it loses color or
becomes contaminated, drain, flush, and replace with
fresh properly mixed coolant solution.
CAUTION: Do not use coolant additives that are
claimed to improve engine cooling.
DESCRIPTION - TRANSFER CASE
Recommended lubricant for the NV241 GENII,
NV271, NV243, NV244 GENII, and NV273 transfer
cases is MopartATF +4, Automatic Transmission
Fluid.
DESCRIPTION - AXLE
NOTE: DaimlerChrysler recommends using MoparT
lubricants or lubricants of equal quality.
FRONT AXLE
²C205F - MopartGear Lubricant 75W-90
²9 1/4 AA - MopartSynthetic Gear Lubricant
75W-90
REAR AXLE
²9 1/4 - MopartSynthetic Gear Lubricant 75W-
140
²10 1/2 AA - MopartSynthetic Gear Lubricant
75W-90
²11 1/2 AA - MopartSynthetic Gear Lubricant
75W-90
NOTE: Trac-LokTdifferentials require Limited Slip
Additive in the lubricant. Trac-RiteŸ differentials
DO NOT require Limited Slip Additive.
DESCRIPTION - MANUAL TRANSMISSION
NOTE: DaimlerChrysler recommends using MoparT
lubricants or lubricants of equal quality.
²NV3500 - MopartManual Transmission Lubri-
cant
²NV4500 - MopartSynthetic 75W85 Manual
Transmission Lubricant
²NV5600 - MopartManual Transmission Lubri-
cant
DESCRIPTION - AUTOMATIC TRANSMISSION
FLUID
NOTE: Refer to Service Procedures in this group for
fluid level checking procedures.
MopartATF +4, Automatic Transmission Fluid is
the recommended fluid for DaimlerChrysler auto-
matic transmissions.
Dexron II fluid IS NOT recommended. Clutch
chatter can result from the use of improper
fluid.
MopartATF +4, Automatic Transmission Fluid
when new is red in color. The ATF is dyed red so it
can be identified from other fluids used in the vehicle
such as engine oil or antifreeze. The red color is not
permanent and is not an indicator of fluid condition.
As the vehicle is driven, the ATF will begin to look
darker in color and may eventually become brown.
This is normal.ATF+4 also has a unique odor that
may change with age. Consequently, odor and color
cannot be used to indicate the fluid condition or the
need for a fluid change.
0 - 4 LUBRICATION & MAINTENANCEDR
FLUID TYPES (Continued)

DIFFERENTIAL & DRIVELINE
TABLE OF CONTENTS
page page
PROPELLER SHAFT......................1
HALF SHAFT...........................20
FRONT AXLE - C205F....................27
FRONT AXLE - 9 1/4 AA...................54REAR AXLE-91/4.......................80
REAR AXLE - 10 1/2 AA..................112
REAR AXLE - 11 1/2 AA..................140
PROPELLER SHAFT
TABLE OF CONTENTS
page page
PROPELLER SHAFT
DIAGNOSIS AND TESTING................1
STANDARD PROCEDURE.................3
SPECIFICATIONS........................6
SPECIAL TOOLS........................6
PROPELLER SHAFT- LD FRONT
REMOVAL.............................6
INSTALLATION..........................7
PROPELLER SHAFT - HD FRONT
REMOVAL.............................7
INSTALLATION..........................7
REAR PROPELLER SHAFT
REMOVAL.............................8
INSTALLATION..........................8CENTER BEARING
REMOVAL.............................9
INSTALLATION..........................9
ADJUSTMENTS.........................9
SINGLE CARDAN UNIVERSAL JOINTS
DISASSEMBLY
DISASSEMBLY - WITH SNAP RINGS......10
DISASSEMBLY - WITH INJECTED RINGS . . . 11
ASSEMBLY
ASSEMBLY - WITH SNAP RINGS.........12
ASSEMBLY - WITH INJECTED RINGS......13
DOUBLE CARDAN UNIVERSAL JOINTS
DISASSEMBLY.........................16
ASSEMBLY............................17
PROPELLER SHAFT
DIAGNOSIS AND TESTING
PROPELLER SHAFT VIBRATION
Out-of-round tires or wheels that are out of bal-
ance, will cause a low frequency vibration.
Driveline vibration can also caused by loose or
damaged engine mounts.Propeller shaft vibration increases with vehicle
speed. A vibration that occurs at a specific speed
range, is not usually caused by an out of balance pro-
peller shaft. Defective universal joints or an incorrect
propeller shaft angle are usually the cause of such a
vibration.
DRDIFFERENTIAL & DRIVELINE 3 - 1

FRONT AXLE - C205F
TABLE OF CONTENTS
page page
FRONT AXLE - C205F
DIAGNOSIS AND TESTING................27
REMOVAL.............................31
INSTALLATION.........................31
ADJUSTMENTS........................32
SPECIFICATIONS.......................39
SPECIAL TOOLS.......................40
AXLE SHAFTS
REMOVAL.............................43
INSTALLATION.........................43
AXLE SHAFT SEALS
REMOVAL.............................43
INSTALLATION.........................43
AXLE BEARINGS
REMOVAL.............................43INSTALLATION.........................44
PINION SEAL
REMOVAL.............................44
INSTALLATION.........................45
DIFFERENTIAL
REMOVAL.............................46
DISASSEMBLY.........................47
ASSEMBLY............................47
INSTALLATION.........................48
DIFFERENTIAL CASE BEARINGS
REMOVAL.............................48
INSTALLATION.........................48
PINION GEAR/RING GEAR
REMOVAL.............................49
INSTALLATION.........................51
FRONT AXLE - C205F
DIAGNOSIS AND TESTING
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 check for:
²Insufficient lubricant.
²Incorrect ring gear backlash.
²Gear damage.
Differential side gears and pinions can be checked
by turning the vehicle. The side gears are loaded dur-
ing turns. They usually do not cause noise during
straight-ahead driving when the gears are unloaded.
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 bearingshave 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.
Differential bearingsusually produce a low pitch
noise. Differential bearing noise is similar to pinion
bearing noise. The pitch of differential bearing noise
is also constant and varies only with vehicle speed.
Axle shaft bearingsproduce 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 m.p.h.
LOW SPEED KNOCK
Low speed knock is generally caused by:
²Worn U-joints/CV joint.
²Worn side-gear thrust washers.
²Worn pinion shaft bore.
DRFRONT AXLE - C205F 3 - 27

ADJUSTMENTS
Ring gear and pinion are supplied as a matched
sets. Identifying numbers for the ring gear and pin-
ion are painted onto the pinion gear shaft and the
side of the ring gear. A plus (+) number, minus (±)
number or zero (0) along with the gear set sequence
number (01 to 99) is on each gear. This first number
is the amount (in thousandths of an inch) the depth
varies from the standard depth setting of a pinion
marked with a (0). The next two numbers are the
sequence number of the gear set. The standard depth
provides the best teeth contact pattern.
Compensation for pinion depth variance is
achieved with select shims located between the rear
pinion bearing cone and pinion gear head (Fig. 6).
If installing a new gear, note the depth variance
number of the original and replacement pinion. Add
or subtract this number from the original depth
shim/oil slinger to compensate for the difference in
the depth variances. The numbers represent thou-
sands of an inch deviation from the standard. If the
number is negative, add that value to the required
thickness of the depth shims. If the number is posi-
tive, subtract that value from the thickness of the
depth shim.
Pinion Gear Depth Variance Chart: Note where
Old and New Pinion Marking columns intersect.
Intersecting figure represents plus or minus the
amount needed.
Fig. 4 DIFFERENTIAL MOUNT
1 - DIFFERENTIAL MOUNT
2 - DIFFERENTIAL HOUSING
3 - MOUNTING BOLTS
Fig. 5 COMPANION FLANGE
1 - COMPANION FLANGE
2 - PROPELLER SHAFT
3 - FLANGE YOKE
4 - REFERENCE MARK
Fig. 6 ADJUSTMENT SHIM
1 - PINION GEAR DEPTH SHIM
2 - DIFFERENTIAL BEARING PRELOAD SHIM
3 - RING GEAR
4 - DIFFERENTIAL BEARING PRELOAD SHIM
5 - COLLAPSIBLE SPACER
3 - 32 FRONT AXLE - C205FDR
FRONT AXLE - C205F (Continued)

PINION GEAR DEPTH VARIANCE
Original Pinion
Gear Depth
VarianceNew Pinion Gear Depth Variance
24232221 0 +1 +2 +3 +4
+4+0.008 +0.007 +0.006 +0.005 +0.004 +0.003 +0.002 +0.001 0
+3+0.007 +0.006 +0.005 +0.004 +0.003 +0.002 +0.001 020.001
+2+0.006 +0.005 +0.004 +0.003 +0.002 +0.001 020.00120.002
+1+0.005 +0.004 +0.003 +0.002 +0.001 020.00120.00220.003
0+0.004 +0.003 +0.002 +0.001 020.00120.00220.00320.004
21+0.003 +0.002 +0.001 020.00120.00220.00320.00420.005
22+0.002 +0.001 020.00120.00220.00320.00420.00520.006
23+0.001 020.00120.00220.00320.00420.00520.00620.007
24020.00120.00220.00320.00420.00520.00620.00720.008
PINION DEPTH MEASUREMENT AND ADJUSTMENT
Measurements are taken with pinion cups and pin-
ion bearings installed in housing. Take measure-
ments with a Pinion Gauge Set, Pinion Block 8177,
Arbor Discs 8541 and Dial Indicator C-3339 (Fig. 7).(1) Assemble Pinion Height Block 6739, Pinion
Block 8177 and rear pinion bearing onto Screw 6741
(Fig. 7).
(2) Insert assembled height gauge components,
rear bearing and screw into the housing through the
pinion bearing cups (Fig. 8).
(3) Install front pinion bearing and Cone-Nut 6740
onto the screw. Tighten cone-nut until Torque To
Rotate the screw is 2.0 N´m (18 in. lbs.) (Fig. 7).
(4) Place Arbor Discs 8541 on Arbor D-115-3 in
position in the housing side bearing cradles (Fig. 9).
Install differential bearing caps on arbor discs and
tighten cap bolts to specification.
(5) Assemble Dial Indicator C-3339 into Scooter
Block D-115-2 and secure set screw.
Fig. 7 PINION GEAR DEPTH GAUGE
1 - DIAL INDICATOR
2 - ARBOR
3 - PINION HEIGHT BLOCK
4 - CONE
5 - SCREW
6 - PINION BLOCK
7 - SCOOTER BLOCK
8 - ARBOR DISC
Fig. 8 PINION HEIGHT BLOCK
1 - PINION BLOCK
2 - PINION HEIGHT BLOCK
DRFRONT AXLE - C205F 3 - 33
FRONT AXLE - C205F (Continued)

FRONT AXLE - 9 1/4 AA
TABLE OF CONTENTS
page page
FRONT AXLE - 9 1/4 AA
DIAGNOSIS AND TESTING................54
REMOVAL.............................57
INSTALLATION.........................58
ADJUSTMENTS........................59
SPECIFICATIONS.......................63
SPECIAL TOOLS.......................64
AXLE SHAFTS
REMOVAL.............................67
DISASSEMBLY.........................68
ASSEMBLY............................69
INSTALLATION.........................69
AXLE SHAFT SEALS
REMOVAL.............................69
INSTALLATION.........................70PINION SEAL
REMOVAL.............................70
INSTALLATION.........................71
DIFFERENTIAL
REMOVAL.............................72
DISASSEMBLY.........................72
ASSEMBLY............................73
INSTALLATION.........................74
DIFFERENTIAL CASE BEARINGS
REMOVAL.............................75
INSTALLATION.........................75
PINION GEAR/RING GEAR
REMOVAL.............................75
INSTALLATION.........................77
FRONT AXLE - 9 1/4 AA
DIAGNOSIS AND TESTING
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 check for:
²Insufficient lubricant.
²Incorrect ring gear backlash.
²Gear damage.
Differential side gears and pinions can be checked
by turning the vehicle. The side gears are loaded dur-
ing turns. They usually do not cause noise during
straight-ahead driving when the gears are unloaded.
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 bearingshave 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.
Differential bearingsusually produce a low pitch
noise. Differential bearing noise is similar to pinion
bearing noise. The pitch of differential bearing noise
is also constant and varies only with vehicle speed.
Axle shaft bearingsproduce 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 m.p.h.
LOW SPEED KNOCK
Low speed knock is generally caused by:
²Worn U-joint(s).
²Worn side-gear thrust washers.
²Worn pinion shaft bore.
3 - 54 FRONT AXLE - 9 1/4 AADR

(7) Connect track bar to the axle bracket and
install the bolt. Do not tighten at this time.
(8) Install shock absorber and tighten bolts to 121
N´m (89 ft. lbs.).
(9) Install stabilizer bar link to the axle bracket.
Tighten the nut to 68 N´m (50 ft. lbs.).
(10) Install drag link and tie rod to the steering
knuckles and tighten the nuts to 108 N´m (80 ft.
lbs.).
(11) Install ABS wheel speed sensors.
(12) Install rotors and brake calipers.
(13) Connect the axle vent hose.
(14) Install front propeller shaft.
(15) With vehicle on the ground, tighten upper
suspension arm nuts at axle to 149 N´m (110 ft. lbs.).
Tighten upper suspension arm nuts at frame to 149
N´m (110 ft. lbs.).
(16) With vehicle on the ground, tighten lower sus-
pension arm nuts at axle to 190 N´m (140 ft. lbs.).
Tighten the lower suspension arm nuts at frame to
190 N´m (140 ft. lbs.).
(17) Tighten track bar bolt at the axle bracket to
176 N´m (130 ft. lbs.).
(18) Check front wheel alignment.
ADJUSTMENTS
Ring and pinion gears are supplied as matched
sets. Compensation for pinion depth variance is
achieved with a select shim. located between the rear
pinion bearing and pinion gear head.
PINION DEPTH MEASUREMENT AND ADJUSTMENT
Measurements are taken with pinion bearing cups
and pinion bearings installed in the housing. Take
measurements with Pinion Gauge Set and Dial Indi-
cator C-3339 (Fig. 6).
(1) Assemble Pinion Height Block 6739, Pinion
Block 8878 and rear pinion bearing onto Screw 6741
(Fig. 6).
(2) Insert assembled height gauge components,
rear bearing and screw into the housing through pin-
ion bearing cups (Fig. 7).
(3) Install front pinion bearing and Cone-Nut 6740
onto the screw. Tighten cone-nut until Torque To
Rotate the screw is 1.7-2.26 N´m (15-20 in. lbs.).
(4) Place Arbor Disc 8289 on Arbor D-115-3 in posi-
tion in the housing side bearing cradles (Fig. 8).
(5) Install differential bearing caps on arbor discs
and snug the bearing cap bolts. Then cross tighten
cap bolts to 85 N´m (63 ft. lbs.).
NOTE: Arbor should rotate freely in the arbor disc.
(6) Assemble Dial Indicator C-3339 into Scooter
Block D-115-2 and secure set screw.(7) Position Scooter Block/Dial Indicator flush on
the pinion height block. Hold scooter block and zero
the dial indicator.
Fig. 6 PINION GEAR DEPTH GAUGE TOOLS
1 - DIAL INDICATOR
2 - ARBOR
3 - PINION HEIGHT BLOCK
4 - CONE
5 - SCREW
6 - PINION BLOCK
7 - SCOOTER BLOCK
8 - ARBOR DISC
Fig. 7 PINION HEIGHT BLOCK
1. PINION HEIGHT BLOCK
2. PINION BLOCK
DRFRONT AXLE - 9 1/4 AA 3 - 59
FRONT AXLE - 9 1/4 AA (Continued)