front diff JEEP CHEROKEE 1988 Service Service Manual

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TR AN SFE R C ASE - N P/N V 2 42

1988 J e ep C hero ke e
1987-96 TRANSFER CASES
Jeep - New Venture 242
Cherokee, Comanche, Wagoneer, Grand Wagoneer
IDENTIFICATION
Transfer case can be identified by an I.D. tag, located on
rear case. I.D. tag provides model number, serial number and low range
ratio. Date of manufacture is the serial number (I.D. number). This
information is necessary when ordering parts.
DESCRIPTION
Model 242 transfer case is a chain-driven, 2-piece aluminum
case, with full time operation. Torque input in 4WD high and low range
is undifferentiated.
ADJUSTMENTS
GEARSHIFT LINKAGE
Remove shift boot and shift to 4L position. Loosen trunnion
nut. Adjust trunnion and shift rod until rod fits freely. Tighten
trunnion nut and remove shim.
TROUBLE SHOOTING
SYMPTOM DIAGNOSIS
Will Not Shift Or Difficult To Shift Into Gear
Check fluid level. Check linkage adjustment. Ensure transfer
case external linkage is not binding. Internal parts may be worn or
damaged.
Noisy In All Gears
Check fluid level. Ensure correct fluid is used. If fluid is
okay, locate noise and check for possible internal mechanical problem.
Jumps Out Of Gear Or Noisy In 4WD
Transfer case not completely in gear; check shift linkage.
Range fork damaged. Inserts are worn. Shift fork binding on shift
rail. Low range gear worn or damaged.
Fluid Leaking From Vent Or Seals
Transfer case overfilled. Vent plugged. Output shaft seals
are damaged or not installed properly.
Transfer Case Will Not Shift Through High Lock Range
Incomplete shift due to driveline torque load; momentarily
release accelerator pedal to complete shift. Check tire pressure and
tire wear. Vehicle overloaded; remove load and check shifting.
ON-VEHICLE SERVICE
FRONT OIL SEAL

intermediate clutch shaft snap ring from mainshaft.
5) Remove clutch shaft thrust ring. Remove intermediate
clutch shaft. Remove differential retaining snap ring. Remove
differential assembly. Remove differential needle bearings and thrust
washers from mainshaft. Remove low range fork and hub.
6) Remove shift sector. Remove shift sector bushing and "O"
ring. Remove front bearing retainer. Remove input gear snap ring.
Using a press, remove input and low range gear assembly from input
gear bearing. Remove low range gear snap ring.
7) Remove input gear retainer, thrust washers and input gear.
Mark differential halves for reassembly purposes. Separate
differential halves. Remove planetary gear and thrust washers.
8) Record mainshaft gear and sprocket gear position. Remove
gears. Remove front output shaft front bearing oil seal, snap ring and
front bearing. Using a press, remove input gear bearing.
9) Using slide hammer and internal puller, remove input gear
pilot bearing. Using slide hammer and internal puller, remove front
output shaft rear bearing.
Fig. 1: Exploded View Of Model 242 Transfer Case
Courtesy of Chrysler Motors.
CLEANING & INSPECTION

1) Clean all parts with solvent. Dry with compressed air.
Replace all oil seals, "O" rings and snap rings. Check all parts for
wear or damage. Replace all worn or damaged parts. Apply Dexron II to
all parts before installing.
2) Inspect low range annulus gear inside front case. If gear
is worn or damaged, replace case and gear as an assembly. Replace oil
pump as an assembly if any part is damaged or worn.
NOTE: When installing bearings, ensure bearing bores are aligned
with oil feed holes.
TRANSFER CASE REASSEMBLY
1) Install front output shaft front bearing, snap ring and
oil seal. Install snap ring on input gear bearing. Using a wooden
block and press, install input gear until snap ring is against case.
2) Install input gear pilot bearing. Assemble low range gear,
thrust washers, input gear and retainer. Install low range gear snap
ring. Ensure snap ring is seated properly in groove.
3) Start input gear shaft through the bearing in front case.
Using a press, install input gear shaft through bearing. Ensure
adapter is positioned properly before pressing shaft.
NOTE: Ensure proper size tool is used to press input gear shaft;
wrong size tool can damage case and thrust washers and will
move pilot bearing too far into gear bore.
4) Install input gear snap ring. Install front bearing
retainer oil seal. Apply 1/8" bead of silicone sealant to front
bearing retainer mating surface. Install front bearing retainer on
front case. Install sector shaft "O" ring and bushing. Install shift
sector.
5) Install detent pin, spring and plug. Install low range
fork pads. Assemble low range fork and hub. Ensure low range fork pin
is engaged in shift sector slot. Install differential sprocket gear in
lower differential case. Install planet gears and new thrust washers
on lower case pins.
6) Ensure thrust washers are positioned on top and bottom of
each planet gear. Install mainshaft gear. Align marks on upper and
lower differential case. Install bolts and tighten to specifications.
See TORQUE SPECIFICATIONS . Install needle bearing spacer on mainshaft.
7) Using petroleum jelly to hold needles, install bearings on
mainshaft. Install other spacer. Install differential assembly. Ensure
all needle bearings are in place. Install differential snap ring.
Install intermediate clutch shaft. Install thrust washer and snap
ring. Install mode shift sleeve in mode fork.
8) Install mode fork assembly on mainshaft. Ensure mode shift
sleeve splines engage with differential splines. Install mode fork and
mainshaft assembly in case. If necessary, rotate mainshaft slightly to
engage mainshaft with low range components.
9) Install mode fork pin into shift sector slot. Install
shift rail. Ensure shift rail is seated in shift forks. Rotate shift
sector so lock pin can be installed. Install lock pin so tapered end
is in fork and rail. Install plug. Install shift lever and nut on
shift sector shaft.
10) Install detent plunger, spring and plug. Install front
output shaft. Install drive chain and sprocket. Install drive sprocket
snap ring. Install front output shaft rear bearing.
11) Install oil seal in oil pump housing. Assemble oil pump
gears in housing. Ensure oil feed hole is aligned with hole in
housing. Install oil pump screws. Tighten to specification. Install

axle backlash. If backlash is one inch or less, drive axle is not the
source of clunk noise.
Bearing Whine
Bearing whine is a high-pitched sound similar to a whistle.
It is usually caused by malfunctioning pinion bearings. Pinion
bearings operate at drive shaft speed. Roller wheel bearings may whine
in a similar manner if they run completely dry of lubricant. Bearing
noise will occur at all driving speeds. This distinguishes it from
gear whine, which usually comes and goes as speed changes.
Bearing Rumble
Bearing rumble sounds like marbles being tumbled. It is
usually caused by a malfunctioning wheel bearing. The lower pitch is
because the wheel bearing turns at only about 1/3 of drive shaft
speed.
Chatter On Turns
This is a condition where the entire front or rear of vehicle
vibrates when vehicle is moving. The vibration is plainly felt as well
as heard. Extra differential thrust washers installed during axle
repair can cause a condition of partial lock-up that creates this
chatter.
Axle Shaft Noise
Axle shaft noise is similar to gear noise and pinion bearing
whine. Axle shaft bearing noise will normally distinguish itself from
gear noise by occurring in all driving modes (Drive, cruise, coast and
float), and will persist with transmission in Neutral while vehicle is
moving at problem speed.
If vehicle displays this noise condition, remove suspect
axle shafts, replace wheel seals and install a new set of bearings.
Re-evaluate vehicle for noise before removing any internal components.
Vibration
Vibration is a high-frequency trembling, shaking or grinding
condition (felt or heard) that may be constant or variable in level
and can occur during the total operating speed range of the vehicle.
The types of vibrations that can be felt in the vehicle can
be divided into 3 main groups:
* Vibrations of various unbalanced rotating parts of the
vehicle.
* Resonance vibrations of the body and frame structures caused
by rotating of unbalanced parts.
* Tip-in moans of resonance vibrations from stressed engine or
exhaust system mounts or driveline flexing modes.
DRIVE AXLE - RWD TROUBLE SHOOTING
NOTE: This is GENERAL information. This article is not intended
to be specific to any unique situation or individual vehicle
configuration. The purpose of this Trouble Shooting
information is to provide a list of common causes to
problem symptoms. For model-specific Trouble Shooting,
refer to SUBJECT, DIAGNOSTIC, or TESTING articles available
in the section(s) you are accessing. For definitions
of listed noises or sounds, see DRIVE AXLE - NOISE DIAGNOSIS
under POWERTRAIN.
DRIVE AXLE (RWD) TROUBLE SHOOTING









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CONDITION POSSIBLE CAUSE CORRECTION

knuckles steering linkage
Rack and pinion mounting Tighten all mounting
loose bolts
Rack and pinion out of See adjustment in
adjustment STEERING article
Tie rod end loose Tighten and check
steering linkage
Excessive Pitman shaft-to- Repair as necessary
ball nut lash









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Poor Lack of lubricant in ball Lubricate and service
Returnability joint or linkage systems
Binding in linkage or ball See STEERING LINKAGE
joints and SUSPENSION article
Improper front end alignment See WHEEL ALIGNMENT
article
Improper tire pressure Inflate to proper
pressure
Tie rod binding Inflate to proper
pressure
Shaft seal rubbing shaft See STEERING COLUMN
article









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Excessive Improper tire pressure Inflate to proper
Vertical Motion pressure
Tires, wheels or rotors Balance tires then
out of balance check wheels and
rotors
Worn or faulty shock Check and replace if
absorbers necessary
Loose tie rod ends or Tighten or replace if
steering necessary
Loose or worn wheel See SUSPENSION article
bearings









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Steering Pulls Improper tire pressure Inflate to proper
to One Side pressure
Front tires are different Rotate or replace if
sizes necessary
Wheel bearings not See FRONT SUSPENSION
article
adjusted properly
Bent or broken suspension See FRONT SUSPENSION
components article
Improper wheel alignment See WHEEL ALIGNMENT
article

or backward tilt from vertical is viewed from side of vehicle. When
axis is tilted backward from vertical, caster is said to be positive,
creating a trailing action on front wheels. When axis is tilted
forward, caster is negative, causing a leading action on front wheels.
Fig. 2: Caster Angle
TOE
Toe is the measured difference in inches of distance between
the front edge of the tires and the rear edge of the tires at spindle
height. Toe can be measured in inches or degrees.
ADJUSTMENT
TOE
1) Measure toe with front wheels straight-ahead and steering
wheel locked in a centered position. Adjust toe by loosening clamps
and adjusting sleeve or adjusting ends on right and left tie rods
equally and in opposite directions to maintain steering wheel in
centered position.
2) If steering wheel is not centered to begin with,
determine which tire assembly is toed in or out more than the other