1999 DODGE RAM lock

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

(1) - Approximate drive axle capacity listed. Lubricant level should
be within 1/2" below bottom of oil filler hole in axle housing
cover.
( 2) - Add container of Mopar Gear Oil Friction Modifier when
refilling.









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FLUID TYPE
Use SAE 80W-90 or SAE 90W hypoid gear lubricant with MIL-L-
2105-B and API GL-5 ratings. Also add a container of Mopar Gear Oil
Friction Modifier when refilling.
FLUID DRAIN & REFILL
1) With lubricant of rear axle assembly at normal operating
temperature, raise and support vehicle so rear wheels are free to
rotate. Clean around axle housing cover. Loosen axle housing cover
bolts. Drain lubricant from axle housing. Remove bolts and axle
housing cover.
2) Position differential so hole in differential case faces
down. Wipe all accessible areas of axle housing. Ensure sealing
surfaces on axle housing and cover are clean. Apply a 1/4" thick bead
of silicone sealant on inside of bolt holes and along sealing surfaces
on axle housing cover.
3) Install axle housing cover, axle identification tag and
retaining bolts. Tighten bolts to 30 ft. lbs. (41 N.m). Remove oil
filler plug. Add a container of Mopar Gear Oil Friction Modifier. Fill
axle with gear lube. Install oil filler plug. Lower vehicle.
TROUBLE SHOOTING
DIFFERENTIAL NOISE
1) Ensure differential lubricant is at normal operating
temperature. Road test vehicle. Note if differential noise exists in
turns, but not during straight-ahead driving. Probable cause is
incorrect or insufficient rear axle lubricant or additive.
2) Drain and refill rear axle. See FLUID DRAIN & REFILL under
LUBRICATION. Road test vehicle and note if noise still exists, it may
be necessary to disassemble rear axle so differential can be repaired.
See RBI FULL-FLOATING AXLES article for removal of differential case.
TESTING
NOTE: Power-Lok differential can be tested without removing
differential carrier from axle housing. Either test can be
used to check drive axle.
TEST I
1) Place blocks under both front wheels. Ensure engine is off
and transmission is in Neutral. Release parking brake. Raise one rear
wheel until it is completely clear of the floor. Remove wheel. Install
Adapter (6790) to wheel studs, and tighten securely.
2) Using torque wrench on adapter, rotate axle, and record
torque required. Repeat procedure for remaining rear wheel position.
If rotational torque for either rear wheel is less than 30 ft. lbs.
(41 N.m) or greater than 200 ft. lbs. (271 N.m), Power-Lok unit must\
be replaced or repaired.

TEST II
1) Drive vehicle until differential lubricant is at normal
operating temperature. Place a piece of Kraft paper over a smooth
Formica board. Place Formica board with Kraft paper under one rear
wheel. Rear wheel should be centered on board on level surface.
2) Block one front tire with a 2" high by 3" wide wooden
block. Start vehicle. With gradual throttle pressure, attempt to
slowly drive vehicle over wooden block.
3) If Kraft paper slips out from under rear wheel before
vehicle drives over wooden block, move Formica board and Kraft paper
under the other rear wheel.
4) With gradual throttle pressure, attempt to slowly drive
vehicle over wooden block again. If vehicle drives over wooden block
with Formica and Kraft paper under either rear wheel, drive axle is
functioning properly.
REMOVAL & INSTALLATION
Servicing procedure is same as that used for a standard
differential. See appropriate RBI FULL-FLOATING AXLES article for
servicing procedures.
OVERHAUL
DIFFERENTIAL CARRIER
CAUTION: Mark all component locations for reassembly reference. Note
position of clutch pack components before removal. Install
clutch pack components in correct order and original
locations.
Disassembly
1) Place reference mark on differential case lower half and
upper half for reassembly reference. Also place reference mark on
pinion cross shaft and differential case lower half for reassembly
reference.
2) Remove differential case half retaining bolts. Remove
differential case upper half. Remove components from differential case
lower half. See Fig. 1.
Fig. 1: Exploded View Of Power-Lok Differential
Courtesy of Chrysler Corp.
Cleaning & Inspection
Clean components with solvent, and dry with compressed air.

DRIV E A XLE - R BI F U LL F LO ATIN G A XLE

1999 D odge P ic ku p R 1500
1998-99 DRIVE AXLES
CHRY - RBI Full-Floating Axles
Ram Pickup, Ram Van/Wagon
IDENTIFICATION
REAR DRIVE AXLE APPLICATION








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Application Axle Ring Axle
Model Gear Size Ratio
Ram Pickup ....... 248 RBI .......... 9.75" ... 3.55:1 Or 4.10:1
Ram Pickup ....... 267 RBI ......... 10.50" ... 3.54:1 Or 4.10:1
Ram Pickup ....... 286 RBI ......... 11.00" ... 3.54:1 Or 4.10:1
Ram Van/Wagon .... 248 RBI .......... 9.75" ... 3.55:1 Or 4.10:1









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DESCRIPTION & OPERATION
The Rear Beam-Design Iron (RBI) axle is an iron center
casting (differential housing) with axle shaft tubes extending from
both sides. The tubes are pressed in to form a one-piece axle housing.
Axle contains an integral carrier with hypoid-type ring gear
and pinion with a solid full-floating axle shaft splined into side
gear. Vehicle weight is supported on tubes of axle housing. Axle
shafts may be serviced without disturbing wheel bearings. On vehicles
equipped with Rear Wheel Anti-Lock (RWAL) brakes, a brake sensor is
mounted on top of axle housing and an exciter ring is mounted on ring
gear.
Axles may be equipped with limited-slip differential. Models
248 and 286 RBI use a Trac-Lok differential and Model 267 RBI uses a
Power-Lok differential as optional equipment. Trac-Lok differential
uses a one-piece case. Power-Lok differential uses a 2-piece case.
Both differentials use same internal components as a standard
differential, except 2 clutch packs are used in the differential case.
NOTE: For servicing of limited-slip differential components in
differential case, see appropriate POWER-LOK or TRAC-LOK
article.
AXLE RATIO & IDENTIFICATION
NOTE: Axle ratio can be identified by axle identification tag
attached to axle housing cover. For axle ratio, see REAR
DRIVE AXLE APPLICATION table at beginning of article.
LUBRICATION
CAPACITY
DRIVE AXLE CAPACITY ( 1)








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Application Pts. (L)\
Ram Pickup
248 RBI ................................................ 6.3 (3.0)\

267 RBI ................................................ 7.0 (3.3)\
286 RBI
2WD ................................................... 6.8 (3.2)\
4WD .................................................. 10.1 (4.8)\
Ram Van/Wagon
248 RBI ................................................ 6.0 (2.8)\
(1) - Approximate drive axle capacity listed. Lubricant level should
be 1/2" below oil filler hole in axle housing cover.









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FLUID TYPE
Use SAE 80W-90 for 286 models, or 90W for all other models,
hypoid gear lubricant with MIL-L-2105-C and API GL-5 ratings. Models
with Trac-Lok require addition of 6 ozs. (.18 L) Mopar(R) friction
modifier (limited slip additive). Ram Pickups equipped with Power-Lok
require addition of 8 ozs. (.24 L) Mopar(R) friction modifier.
TROUBLE SHOOTING
NOTE: See appropriate table in TROUBLE SHOOTING article in GENERAL
INFORMATION.
REMOVAL & INSTALLATION
REAR HUB, BEARINGS & AXLE SHAFT
Removal
Raise and support vehicle. Remove wheel. Remove bolts, axle
shaft and gasket. Remove nut lock from adjusting nut. See Fig. 1.
Remove adjusting nut and outer wheel bearing. Remove rear hub and
brake drum. Remove oil seal and inner wheel bearing (if necessary).
Installation
1) Pack wheel bearings with wheel bearing grease. Install
inner wheel bearing and oil seal in rear hub (if removed). Install
rear hub and brake drum. Install outer wheel bearing and adjusting
nut. Tighten adjusting nut to specification while rotating rear hub
and brake drum. See TORQUE SPECIFICATIONS table.
2) Back off adjusting nut approximately 1/8 turn to obtain .
001-.010" (.03-.25 mm) wheel bearing end play. Tap key lock into
adjusting nut and keyway on axle housing.
3) To install remaining components, reverse removal
procedure. Use NEW gasket when installing axle shaft. Tighten bolts to
specification. See TORQUE SPECIFICATIONS table.
DRIVE SHAFT
Removal
1) Raise and support vehicle. Ensure transmission and
transfer case selector levers are in Neutral. Remove wheel assembly.
Remove RWAL sensor, if equipped. Reference mark drive shaft to pinion
flange for reassembly.
2) On 2-piece drive shafts, scribe center carrier bearing-to-
frame bracket reference line for reassembly. On all drive shafts,
remove bolts and "U" joint straps at pinion flange. Remove center
carrier bearing bolts, if equipped. Remove spring clamps and brackets.
Remove drive shaft(s).
CAUTION: The "U" joint straps and bolts must be replaced. DO NOT

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.
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.
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) Block brake pedal in upward position, as brake fluid lines
must be disconnected. Raise and support vehicle at body, in front of
rear springs. Remove rear wheels.
2) Reference mark drive shaft to pinion flange for
reassembly. Remove bolts and "U" joint straps at pinion flange. Remove
drive shaft, and support aside.
3) Disconnect and plug brakelines. Disconnect parking brake
cables. Disconnect shock absorbers. On models with Rear Wheel Anti-
Lock (RWAL) brakes, disconnect electrical connector at brake sensor on\
top of axle housing.
4) On all axles, support axle housing assembly with floor
jack. Remove rear spring "U" bolts. Lower axle housing assembly and
remove from vehicle.
Installation
1) To install, reverse removal procedure. Ensure rear spring
center bolts align with holes in spring pads on axle housing assembly.
2) Ensure reference marks on drive shaft and pinion flange
align. Tighten bolt/nuts to specification. See TORQUE SPECIFICATIONS.
Bleed and adjust brakes. Check axle fluid level and fill if necessary.
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) On axles with Rear Wheel Anti-Lock (RWAL) brakes, remove
brake sensor from top of axle housing. On all axles, remove axle
shafts from differential. See REAR HUB, BEARINGS & AXLE SHAFT 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 bearing caps. Place Axle Housing Spreader (W-129-B)\
on axle housing so dowel pins engage with locating holes. See Fig. 2.
Install hold-down clamps. Finger tighten turnbuckle on axle housing
spreader.
4) Install Guide Pin (C3288-B) at left side of axle housing.\

Install pilot stud and dial indicator onto axle housing. Position dial
indicator so stem is resting against opposite side of axle housing,
with pressure on stem.
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).
CAUTION: DO NOT spread axle housing more than .020" (.50 mm), or axle
housing may be damaged.
Fig. 2: 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 same 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) On rear axles with Rear Wheel Anti-Lock (RWAL) brakes, us\
e
soft-face hammer to tap exciter ring from differential case if
removing exciter ring. Replace exciter ring if removed from
differential case.
9) On all axles, remove pinion nut and washer from pinion.
Scribe reference mark on pinion flange and pinion if components are to
be reused. Disconnect drive shaft, and wire aside.
10) Using appropriate holder and flange remover, remove