1998 MITSUBISHI MONTERO Service Manual

DIFFERENTIAL & AXLE SHAFTS REAR
1998 Mitsubishi Montero
1997-98 DRIVE AXLES
Mitsubishi Differentials & Axle Shafts - Rear Non-Integral
Montero, Montero Sport
DESCRIPTION
Rear axle features a rigid banjo-type housing with semi-
floating axle shafts. Differential consists of hypoid reduction gears
and straight bevel differential gears. Limited Slip Differential (LSD)\
is available on some models. Locking rear differential is available on
1997-98 Montero and 1998 Montero Sport. See DIFFERENTIAL LOCK - REAR
article.
AXLE RATIO & IDENTIFICATION
Ratio is determined by dividing number of ring gear teeth by
number of drive pinion teeth.
AXLE RATIO SPECIFICATIONS









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Application Ratio
Montero ..................................................... 4.27:1
Montero Sport
With Wide Fender
2WD ..................................................... 4.22:1
4WD ..................................................... 4.27:1
Without Wide Fender ....................................... 4.64:1









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LUBRICATION
CAPACITY
REAR AXLE GEAR OIL CAPACITY








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Application Pts. (L)\
Montero .................................................. 6.8 (3.2)\
Montero Sport
Conventional & Locking ................................. 3.2 (1.5)\
Limited Slip ........................................... 5.5 (2.6)\









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FLUID TYPE
Conventional differentials use SAE 80W or SAE 90W API GL-5.
Limited slip differentials use Mitsubishi Gear Oil (8149630 EX), or
Mopar Gear Oil (4318058) and Mopar Friction Modifier (4318060).
TROUBLE SHOOTING
NOTE: See TROUBLE SHOOTING - BASIC PROCEDURES article in the
GENERAL TROUBLE SHOOTING section.

TESTING & INSPECTION
AXLE SHAFT END PLAY
Montero & Montero Sport
Using dial indicator, check axle shaft end play. End play
should be .010" (.25 mm). If end play is not within specification,
replace axle bearing. See AXLE SHAFT OVERHAUL under OVERHAUL.
AXLE TOTAL BACKLASH
1) Raise and support rear axle. Place transmission in
Neutral. Apply parking brake. Rotate drive shaft clockwise. Place
reference marks on pinion dust cover and differential housing.
2) Rotate drive shaft counterclockwise, and measure distance
between reference marks. Differential must be removed and backlash
adjusted if distance exceeds 0.2" (5 mm). See RING GEAR BACK-LASH
procedure under DIFFERENTIAL ASSEMBLY (LIMITED SLIP) under OVERHAUL.
LIMITED SLIP DIFFERENTIAL PRELOAD
1) Place transmission in Neutral. Block front wheels. Raise
one rear wheel off ground and remove wheel. Release parking brake.
2) Using torque wrench and axle puller adapter, measure
starting torque while rotating wheel in forward direction. See Fig. 1.
Differential must be repaired if torque is less than 18 ft. lbs. (25
N.m).
Fig. 1: Testing Limited Slip Differential Preload
Courtesy of Mitsubishi Motor Sales of America.
LOCKING DIFFERENTIAL (MONTERO)
Air Pump

Connect air pressure gauge in-line to air hose from air pump.
Air pump is located in right storage area, under rear seat. Connect
battery voltage to air pump (positive lead to Red wire). The air pump
is operating correctly when the following sequences occur;
* Pump should operate for no more than 5 seconds.
* Pressure should be 4-6 psi (.28-.41 kg/cm
) within 10-20
seconds after pump has stopped.
* After air pump has stopped operating, it should not restart
operating for 5 minutes.
Center Differential Lock Operation Switch
See ANTI-LOCK BRAKE SYSTEM article in BRAKES.
Differential Lock Switch
Remove switch from center console. To test switch operation,
see Fig. 2 . Replace switch as needed.
Differential Lock Control Unit
See ANTI-LOCK BRAKE SYSTEM article in BRAKES.
Lock Detection Switch
1) Raise and support vehicle. Disconnect air hose connection
near rear differential. Connect air source with pressure regulator and
pressure gauge. Apply 4 psi (.28 kg/cm
) pressure. Disconnect lock
detection switch harness connector.
2) Using ohmmeter, check if continuity exists with air
pressure applied. Continuity should exist with air pressure applied.
If continuity exists, ensure axle is locked by attempting to turn rear
wheels separately of each other.
3) If continuity does not exist, go to step 4). If continuity\
does exist but axles are not locked, see CARRIER ASSEMBLY under
REMOVAL & INSTALLATION and inspect locking assembly.
4) Remove detection switch from housing. Using ohmmeter,
check continuity of switch. Continuity should exist with switch
plunger extended. With plunger in neutral position, continuity should
not exist. Replace switch as needed.
Fig. 2: Checking Differential Lock Switch Continuity
Courtesy of Mitsubishi Motor Sales of America.
REMOVAL & INSTALLATION

AXLE SHAFT R & I
Removal (Montero & Montero Sport)
Block front wheels. Raise and support rear axle housing.
Remove brake caliper and rotor. See Fig. 3. Remove parking brake cable
attaching bolts. Remove connection for parking brake cable end from
rear brake assembly. Remove ABS speed sensor (if equipped). Unbolt
backing plate with bearing housing from rear axle housing. Using
Puller (MB990241) and Slide Hammer (MB990211), remove axle assembly.\
DO NOT damage oil seal. Remove "O" ring. Replace if necessary.
Installation
Install NEW oil seal in axle housing as needed. To install
axle assembly, reverse removal procedure.
Fig. 3: Exploded View Of Typical Axle Shaft
Courtesy of Mitsubishi Motor Sales of America.
Installation
1) Insert new "O" ring and shim of .04" (1.0 mm) thickness

into left side axle housing. Install left axle shaft assembly into
axle housing, and tighten nuts to specification. See
TORQUE SPECIFICATIONS.
2) Install right axle shaft assembly into axle housing
without shim or "O" ring. Temporarily tighten nuts in diagonal
sequence to 51.6 INCH lbs. (5.8 N.m) in 2 stages. Measure clearance
between bearing case of right axle and rear axle housing end with
feeler gauge.
3) Select shims equal to sum of measured clearance plus .002-
.008" (.05-.20 mm). Remove right axle shaft, and install selected
shim(s) and "O" ring into right axle housing end. Install right axle
shaft assembly into rear axle housing. Tighten nuts in diagonal
sequence to specification. See TORQUE SPECIFICATIONS.
4) Using dial indicator, check end play of axle shaft. End
play should be .002-.008" (.05-.20 mm). If end play is not within
specification, change shim(s) to obtain correct end play. Reverse
removal procedure to install remaining components. Adjust parking
brake, and bleed brake system.
CARRIER ASSEMBLY
Removal
Raise and support vehicle. Drain gear oil. Mark drive shaft
flange-to-pinion flange position. Remove drive shaft. Remove axle
shafts. See AXLE SHAFT R & I . Support differential carrier with jack.
Remove differential carrier retaining nuts. Remove differential
carrier.
Inspection
Check for leaks at vent plug, differential carrier companion
flange and where carrier joins axle housing.
Installation
Apply sealant to axle housing surface. To install, reverse
removal procedure. Align marks on drive shaft and pinion flange.
DRIVE SHAFT
Removal
Make match marks on drive shaft yoke flange and pinion
flange. Remove bolts and drive shaft from vehicle.
Installation
To install, reverse removal procedure. Ensure match marks are
aligned. Tighten bolts to specification. See TORQUE SPECIFICATIONS.
OVERHAUL
AXLE SHAFT OVERHAUL
Removal
1) Secure axle shaft assembly in a vise, and remove one
retainer bolt from backing plate. Push bearing case completely to side
of dust cover. Place adhesive tape around edge of bearing case at
retainer bolt hole to prevent damage.
CAUTION: DO NOT damage bearing case or axle shaft when grinding or
chiseling retainer ring.
2) Secure axle shaft, and grind retainer ring until retainer
ring wall thickness is .04-.06" (1.0-1.5 mm) on axle shaft side and .
08" (2.0 mm) on bearing side. See Fig. 4.

3) Change angle of grind, and remove remaining .08" (2.0 mm)\
of retainer ring wall on bearing side. Using a chisel, cut retainer
ring. Remove ring. DO NOT damage axle shaft.
4) Install Puller (MB990787-01) to remove bearing case from
axle shaft. See Fig. 5. Rotate nuts with equal force to remove wheel
bearing. Remove bearing outer race using a hammer and drift. Remove
oil seal from axle housing using a slide hammer and hook.
Fig. 4: Grinding Bearing Retainer Ring
Courtesy of Mitsubishi Motor Sales of America.

Fig. 5: Removing Bearing Case From Axle Shaft
Courtesy of Mitsubishi Motor Sales of America.
Inspection
Inspect bearings for roughness, pitting or damage. Inspect
axle shaft for damaged splines or flange. Inspect bearing case for
cracks or damage.
Installation
1) Apply Multipurpose Grease (SAE J310) to oil seal, oil sea\
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cavity and contact surfaces. Install oil seal using seal driver. Press
new oil seal into bearing case until it is flush with face of bearing
case. Install backing plate and bearing case.
2) Apply grease to external surfaces of bearing outer race.
Press bearing outer race into bearing case. Install bearing on axle
shaft. Install rear brake assembly with bearing case onto axle.
Install inner bearing on axle. Install NEW retainer ring. Do not
exceed 22,046 lbs. (100,00 N) when pressing on retainer ring. Install
NEW snap ring.
3) Using a feeler gauge, measure clearance between snap ring
and NEW retainer ring. Clearance should be less than .007" (.17 mm).
If clearance exceeds specification, install correct snap ring. See
SNAP RING THICKNESS SPECIFICATION table.
SNAP RING THICKNESS SPECIFICATION









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Thickness: In. (mm) Color\

.060 (1.52) .................................................... Red\
.067 (1.70) ................................................. Purple\
.073 (1.85) ................................................... Blue\
.079 (2.01) ................................................. Yellow\
.085 (2.16) ................................................ Neutral\









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DIFFERENTIAL ASSEMBLY (CONVENTIONAL)
Pre-Disassembly Inspection
1) Secure differential assembly in appropriate holder. Secure
drive pinion from turning. Mount dial indicator on case and check ring
gear backlash at 4 positions. See Fig. 6. Backlash should be .005-.
007" (.13-.18 mm).
2) Remount dial indicator and measure ring gear runout. See
Fig. 7 . On all models, runout should not exceed .002" (.05 mm).
Remount dial indicator and measure pinion gear backlash on models
without limited slip differential. See Fig. 8. Secure side gear from
turning with wedge. Backlash should be 0-.003" (0-.08 mm). Pinion gear\
backlash service limit is .008" (.20 mm).
3) Check gear tooth contact pattern between ring gear and
drive pinion gear. Apply Prussian Blue to both surfaces of ring gear
teeth. Insert brass rod between differential housing and carrier
assembly to provide resistance while turning drive pinion.
4) Turning resistance of drive pinion should be 28-33 INCH
lbs. (2.5-3.0 N.m). Rotate drive pinion until ring gear completes one
revolution. Reverse direction of rotation and return to original
starting point. Check wear pattern. See GEAR TOOTH CONTACT PATTERNS
article in GENERAL INFORMATION.
5) On Montero models with differential lock, connect air
supply hose with pressure gauge and regulator to actuator air pipe.
Apply 4 psi (.28 kg/cm
) of pressure. Using Adapter Shaft (MB990992),
turn side gear on one side of carrier assembly only. Locking mechanism
should engage. To disengage, release air pressure and turn side gear
1/4-1/2 turn.
6) With lock mechanism engaged, measure turning torque of
drive pinion. Turning torque should not be less than 36 ft. lbs. (50
N.m). With lock mechanism disengaged, turning torque should not be
more than 36 ft. lbs. (50 N.m).
Fig. 6: Measuring Ring Gear Backlash
Courtesy of Mitsubishi Motor Sales of America.