1988 JEEP CHEROKEE weight

NOTE: Crankshaft journal diameters are indicated by a color coded
mark placed on the adjacent counterweight or cheek toward
the flanged (rear) end of crankshaft. Note color code to
determine proper bearing usage. Check oil clearance after
bearing installation.
Removal
1) Remove oil pan. See OIL PAN REMOVAL at end of ENGINE
section. See oil pump. See OIL PUMP under ENGINE OILING. Remove main
bearing cap.
2) Rotate crankshaft to position rod to be serviced at bottom
of stroke. Mark bearing cap and connecting rod. Remove bearing cap
with bearing. Push piston and rod assembly up to remove upper bearing.
Installation
1) Note color code on edge of bearings removed. Install
bearings. Using Plastigage method, check bearing clearances. Replace
bearings as necessary to obtain correct clearance. Bearings are
available in standard and undersize application.
2) If required, different sized upper and lower bearings may
be installed to obtain correct oil clearance. Tighten bolts to
specification. Check rod side play. Rotate crankshaft to ensure
freedom of movement. Reverse removal procedures for remaining
components. Tighten bolts to specification.
NOTE: Avoid combining bearing inserts in excess of .001" (.02 mm)
difference in size. Odd size inserts must be on bottom (rod
cap) side.
MAIN BEARINGS
Removal
1) Remove oil pan. See OIL PAN REMOVAL at end of ENGINE
section. Remove oil pump. See OIL PUMP under ENGINE OILING.
2) Ensure main bearing caps are marked for location. Rotate
crankshaft to remove bearings. Note color code on edge of bearing.
NOTE: Crankshaft journal diameters are indicated by a color coded
mark placed on the adjacent counterweight or cheek toward
the flanged (rear) end of crankshaft. Note color code to
determine proper bearing usage. Check oil clearance after
bearing installation.
Installation
1) Note color code on edge of bearings removed. Install
bearings. Ensure caps are installed in original location. Using
Plastigage method, check bearing clearances.
2) Replace bearings as necessary to obtain correct clearance.
Bearings are available in standard and undersize applications. If
required, different sized upper and lower bearings may be installed to
obtain correct oil clearance.
NOTE: If different sized bearings are used, the odd sized bearings
must all be uniform in location (upper or lower). DO NOT use
bearings with a thickness difference exceeding .001" (.02
mm).
3) Apply Loctite to corners of rear main bearing cap prior to
final installation. Tighten bolts to specification. Check crankshaft
end play. See CRANKSHAFT END PLAY. Rotate crankshaft to ensure freedom
of movement. Reverse removal procedures for remaining components.
Tighten bolts to specification.

ROD BEARING
NOTE: Crankshaft journal diameters are indicated by a color coded
mark placed on the adjacent counterweight or cheek toward
the flanged (rear) end of crankshaft. Note color code to
determine proper bearing usage. Check oil clearance after
bearing installation.
Removal
Remove oil pan. See OIL PAN REMOVAL at end of ENGINE section.
Rotate crankshaft to position rod to be serviced at bottom of stroke.
Mark bearing cap and connecting rod. Remove bearing cap with bearing.
Push piston and rod assembly up to remove upper bearing.
Installation
1) Note color code on edge of bearings removed. Install
bearings. Using Plastigage method, check bearing clearances. Replace
bearings as necessary to obtain correct clearance. Bearings are
available in standard and undersize application.
2) If required, different sized upper and lower bearings may
be installed to obtain correct oil clearance. Tighten bolts to
specification. Check rod side play. Rotate crankshaft to ensure
freedom of movement. Reverse removal procedure for remaining
components. Tighten bolts to specification.
NOTE: Avoid combining bearing inserts in excess of .001" (.02 mm)
difference in size.
MAIN BEARING
Removal
Remove oil pan. See OIL PAN REMOVAL at end of ENGINE section.
Ensure main bearing caps are marked for location. Remove bearing cap.
Rotate crankshaft to remove bearings. Note color code on edge of
bearing.
NOTE: Crankshaft main bearing journal diameters are indicated by a
color code. Color code is placed on the adjacent cheek
toward the flanged (rear) end of crankshaft for all except
the rear main. Rear main is color coded on the rear flange.
Note color code to determine proper bearing usage. Check oil
clearance after bearing installation.
Installation
1) Note color code on edge of bearings removed. Install
bearings. Ensure caps are installed in original location with arrow on
cap facing toward front of engine. Using Plastigage method, check
bearing clearances.
2) Replace bearings as necessary to obtain correct clearance.
Bearings are available in standard and undersize applications. If
required, different sized upper and lower bearings may be installed to
obtain correct oil clearance.
NOTE: If different sized bearings are used, odd sized bearings must
all be uniform in location (upper or lower). DO NOT use
bearings with a thickness difference exceeding
.001" (.02 mm).
3) Tighten bolts to specification. Check crankshaft end play.
See CRANKSHAFT END PLAY in this article. Rotate crankshaft to ensure
freedom of movement. Reverse removal procedure for remaining
components. Tighten bolts to specification.

Ign. Ignition 

In. Inches 

Inj. Injector 











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"J" ABBREVIATION TABLE
"J" ABBREVIATION TABLE







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ABBREVIATION DEFINITION 










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J/B Junction Block 











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"K" ABBREVIATION TABLE
"K" ABBREVIATION TABLE







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ABBREVIATION DEFINITION 










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k/ohms 1000 ohms (kilo as in k/ohms) 

kg Kilograms (weight) 

kg/cm Kilograms Per Square Centimeter 

KAM Keep Alive Memory 

KAPWR Keep Alive Power 

KM/H Kilometers Per Hour 

KOEO Key On Engine Off 

KOER Key On Engine Running 

KS Knock Sensor 











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"L" ABBREVIATION TABLE
"L" ABBREVIATION TABLE







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ABBREVIATION DEFINITION 










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L Liter(s) 

L/D Light Duty 

LCD Liquid Crystal Display 

LED Light Emitting Diode 

LH Left Hand 

LOS Limited Operation Strategy 

LT BLU Light Blue 

LT GRN Light Green 

LUS Lock-Up Solenoid 

Lbs. Pounds 

Lt(s). Light(s) 

Lugg. Luggage 











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"M" ABBREVIATION TABLE
"M" ABBREVIATION TABLE







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ABBREVIATION DEFINITION 










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mA Milliamps 

mV Millivolts 

mfd. Microfarads 

same axle to eliminate uneven braking behavior. Always wash drums
after servicing or before installing.
DRUM INSPECTION









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Condition Code Procedure
Balance weight missing .. .. ........ No service suggested or
required.
Bell-mouthed, affecting
performance ............ A ....... Require reconditioning or
replacement.
Cooling fin broken ...... .. ........ No service suggested or
required.
Cracked ................. B ............ Require replacement.
Drum diameter is greater
than OEM "machine to"
specifications but less
than "discard at"
specifications, and the
drum does not require
reconditioning ......... 1 ........ (1) Suggest replacement.
Drum diameter will exceed
OEM "machine to"
specifications after
required
reconditioning ......... B ........ ( 2) Require replacement.
Hard-spotted ............ 2 ....... Suggest reconditioning or
replacement.
Measured diameter is
greater than OEM discard
specifications ......... B ............ Require replacement.
Out-of-round (runout),
affecting performance .. A ....... Require reconditioning or
replacement.
Out-of-round (runout),
exceeding manufacturer's
specifications ......... B ....... Require reconditioning or
replacement.
Scored .................. B ....... Require reconditioning or
replacement.
Surface threaded due to
improper machining ..... B ....... Require reconditioning or
replacement.
Tapered, affecting
performance ............ A ....... Require reconditioning or
replacement.
( 1) - Only applies to vehicles for which OEM "machine to"
specifications exist. If OEM does not supply "machine to"
specifications, the drum may be worn to discard
specifications.
( 2) - If OEM does not supply "machine to" specifications, you
may machine to discard specifications.









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ELECTRICAL PUMPS AND MOTORS
Copied fuel pump conditions from engine UIGs & deleted
pulsator from leaking conditions.
ELECTRICAL PUMP AND MOTOR INSPECTION









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and reinstalled. Brake shoes can be manually adjusted by rotating
adjuster screw. Remove access slot cover.
3) Using a small blade screwdriver, push in on adjustment
lever to separate from adjustment screw. Turn adjustment screw until
brake drum is locked tight. Back screw off until wheel rotates freely.
If brake drum is to be removed, back off adjustment screw several
notches for adequate clearance.
HEIGHT SENSING PROPORTIONING VALVE - COMANCHE
NOTE: Anytime adjustment is required the lever bushing must be
replaced.
Adjustment must be made on a drive-on lift or a flat level
surface with vehicle at curb weight. Remove height sensing
proportioning valve shaft nut and washer. Disconnect valve lever and
remove spring. Remove and discard bushing.
Rotate valve shaft to permit installation and proper
alignment of valve adjusting gauge (J-35853-2).
NOTE: The gauge (J-35853-2) must be properly seated on the "D"
shape of the shaft and the lower mounting bolt of the valve.
See Fig. 2. Also, all linkage components, excluding the
spring, must be connected to the axle housing before
installation of bushing.
Place lever bushing in lever. Using bushing installation
tool (J-35853-1) press bushing along with lever onto valve shaft.
Remove lever and adjusting to (J-35853-2) then install the spring.
Install lever, washer and retaining nut. Tighten retaining nut to 100
Inch-lbs. (11 N.m). Connect spring to lever arm.
Fig. 1: Exploded View of Height Sensing Proportioning Valve

lubricant to axle flange bearing bore and install axle.
YOKE & PINION OIL SEAL
Removal
1) Raise and support vehicle. Remove wheels and brake drums.
Mark and remove drive shaft. Using an INCH lb. torque wrench, record
torque required to rotate pinion several revolutions.
2) Hold yoke from turning and remove pinion nut. Mark drive
pinion shaft and yoke for reassembly reference. Remove yoke and pinion
oil seal.
Installation
1) Coat new seal with rear axle lubricant and install. Align
marks made at disassembly and install yoke. Install new pinion nut and
tighten just enough to remove end play.
CAUTION: DO NOT overtighten pinion nut. If desired preload is
exceeded, a new collapsible pinion spacer sleeve must be
installed and drive pinion preload reset.
2) Using an INCH lb. torque wrench, check torque required to
turn pinion. Refer to torque reading recorded during disassembly and
add 5 INCH lbs. (.6 N.m) for correct preload. Tighten pinion nut
slightly and recheck preload. Repeat procedure until desired preload
is obtained.
REAR AXLE ASSEMBLY
Removal
1) Raise and support vehicle. Remove wheels and brake drums.
Disconnect brake hose-to-axle connection and plug line.
2) Disconnect parking brake cable at brake equalizer. Mark
and remove drive shaft. Disconnect track bar at axle bracket (if
equipped). Remove axle vent tube at axle. Support axle assembly.
Remove spring "U" bolts and tie plates.
3) Loosen, but do not remove, bolts which attach front of
rear spring to frame brackets. Lift axle to relieve axle weight from
springs and remove bolts retaining springs to shackles. Lower springs
to floor. Lower jack and remove axle assembly.
NOTE: Factory axles are shipped without lubricant. When adding
lubricant, position axle horizontally with yoke end of
pinion housing facing downward. Turn pinion shaft several
times to lubricate bearings.
Installation
1) To install, support axle assembly with jack and slide axle
into place. Raise, align and install spring-to-frame and shackle
bolts. Tighten spring-to-frame and shackle bolts to 111 ft. lbs. (150
N.m). Install brake hose, axle vent tube and parking brake cable.
Align and connect drive shaft.
2) Bleed hydraulic system and adjust parking brake cable.
Ensure axle is filled with 75-90W gear lubricant. Ensure spring
centering bolt heads are seated in axle spring seat before tightening
"U" bolts.
OVERHAUL
DISASSEMBLY
NOTE: It is not necessary to remove axle assembly from vehicle to

2) On models with 2-piece shafts, rotate transmission yoke
until trunnion is in horizontal plane. Install front drive shaft with
"U" joint trunnion in vertical plane. Connect bearing support to
crossmember.
3) Ensure that front face of bearing support is perpendicular
(90 degrees) to centerline of drive shaft. Install rear drive shaft
with "U" joint trunnion of slip joint in vertical plane.
4) Set differential pinion yoke trunnion in vertical plane.
Connect rear drive shaft to pinion yoke. If 2-piece shaft is correctly
installed, centerline of trunnions at each end of individual shafts
will be parallel. See Fig. 3.
Fig. 3: Phase Alignment Of 2-Piece Drive Shafts
Trunnion yoke ears on each shaft must be parallel.
DRIVE SHAFT BALANCE TEST
1) Drive shaft imbalance may often be cured by disconnecting
shaft and rotating it 180 degrees in relation to other components.
Test by raising rear wheels off ground, and turning shaft with engine.
NOTE: DO NOT run engine without ram airflow across radiator for
prolonged periods, as overheating of engine or transmission
may occur.
2) On most models, balance testing may be done by marking
shaft in 4 positions, 90 degrees apart. Place marks approximately 6"
forward of weld, at rear end of shaft. Number marks one through 4.
3) Place screw-type hose clamp so clamp head is in number one
position, and rotate shaft with engine. If there is little or no
change, move clamp head to No. 2 position, and repeat test.
4) Continue procedure until vibration is at lowest level. If
no difference is noted with clamp head moved to all 4 positions,
vibrations may not be drive shaft imbalance.
5) If vibration is lessened but not completely gone, place 2
clamps at that point, and run test again. Combined weight of clamps in
one position may increase vibration. If so, rotate clamps 1/2" apart,
above and below best position, and repeat test.
6) Continue to rotate clamps as necessary, until vibration is
at lowest point. If vibration level is still unacceptable, leave rear
clamp(s) in position and repeat procedure at front end of drive shaft.\
If vibration can be eliminated or reduced to acceptable levels using
this test procedure, send drive shaft out to be balanced.

Condition Code Procedure
Application incorrect ... B .. Require repair or replacement.
Cracked ................. A .. Require repair or replacement.
Distorted ............... A .. Require repair or replacement.
Missing ................. C ............ Require replacement.
Positioned incorrectly .. B .. Require repair or replacement.
Stepped ................. A .. Require repair or replacement.
Worn to the extent that it
no longer performs its
intended function ...... A .. Require repair or replacement.









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DRIVE SHAFT FLANGES
See COMPANION FLANGES .
DRIVE SHAFTS AND HALF SHAFTS
DRIVE SHAFT AND HALF SHAFT INSPECTION








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Condition Code Procedure
Balance weight missing .. C .. Require repair or replacement.
Bearing cap bore
distorted .............. A .. Require repair or replacement.
Bent .................... A ............ Require replacement.
Bolt holes elongated .... A .. Require repair or replacement.
Bushing or seal surface
worn, affecting
performance ............ A .. Require repair or replacement.
Leaking through soft yoke
plug ................... A ... Require repair or replacement
of soft yoke plug.
Out of balance .......... A .. Require repair or replacement.
Retainer strap bent ..... A .......... Require replacement of
retainer strap.
Slip yoke broken ........ A ............ Require replacement.
Splines worn, affecting
performance ............ A ............ Require replacement.
Splines worn close to
the end of their
useful life ............ 1 ............ Suggest replacement.
Threads damaged ......... A .. Require repair or replacement.
Threads stripped (threads
missing) ............... A ............ Require replacement.
U-bolt damaged, affecting
performance ............ A . Require replacement of U-bolts.
Yoke damaged, affecting
performance ............ A .. Require repair or replacement.









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DUST BOOTS
NOTE: Does not include CV boots.
DUST BOOT INSPECTION









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Condition Code Procedure
Cracked, not leaking .... 1 ............ Suggest replacement.
Missing ................. C ............ Require replacement.
Leaking ................. A .. Require repair or replacement.