JEEP CHEROKEE 1994 Service Repair Manual

CONSTRUCTION
The frame is constructed of high-strength channel
steel siderails and crossmembers. The crossmembers
join the siderails and retain them in alignment in re-
lation to each other. This provides resistance to
frame twists and strains.
FRAME ALIGNMENT
INCORRECT ALIGNMENT
Incorrect frame alignment is usually a result of:
²collision impact, or
²the vehicle being operated with excessive loads, or
²loads not positioned in a properly distributed man-
ner on the vehicle.
A mis-aligned frame will affect front axle and/or
rear axle alignment. It can cause excessive wear and
mechanical failures in the powertrain. Window glass
cracks and door opening/closing problems. Vehicle
performance can also be impaired.
RE-ALIGNMENT
With collision damage, it is important that the ex-
istence of any frame alignment damage be deter-
mined. If necessary, the frame should be correctly re-
aligned. Refer to the reference dimensions listed on
frame alignment dimension chart (Fig. 4).
FRAME INSPECTION/MEASUREMENTS
INSPECTION
Before proceeding with measurements, inspect all
components for visible damage and other metal dam-
age. Also, inspect all connections for loose and miss-
ing hardware.
All damaged areas must be repaired and/or the
components replaced, as necessary.
MEASUREMENTS
Measure the frame for mis-alignment with the
body attached to the frame. Figure 4 provides the
alignment reference dimensions. The following infor-
mation applies to all measurements.
(1) Place the vehicle on a level surface.
(2) If the vehicle is loaded, ensure that the vehicle
weight plus the payload does not exceed the gross ve-
hicle weight rating. Also, ensure that the load is dis-
tributed in the vehicle as evenly as possible.
(3) Measure the tire inflation pressures and adjust
the pressure, if necessary.
HORIZONTAL OR DIAGONAL FRAME MEASUREMENTS
Determine the frame horizontal non-square devia-
tion(s) according to the following procedure.
(1) Select several reference points along one frame
siderail, preferably at the crossmember junctions.(2) Transfer these reference points to the surface/
floor with a plumb bob. Paper sheets can be attached
to the surface below the reference points for better
measurement accuracy.
(3) Locate the reference points on the other frame
siderail and transfer them to the surface/floor with
the same procedure as above.
(4) Move the vehicle away and measure between
all the reference points diagonally from and parallel
to the siderails (Fig. 5). The measurements should
not differ by more than 6 mm (1/4 in).
(5) Measure the distance between the two front
reference points and the distance between the two
rear reference points. Divide each distance in half
and indicate the two half-way points on the surface/
floor. Designate the front point as ``1'' and the rear
point as ``2'' (Fig. 5).
(6) Place a chalk-line between points 1 and 2 and
``snap'' the string.
(7) Determine how close the center line is to the
diagonal intersection points A, B, C, D, E, and F in
Figure 5.
(8) The reference marks on the surface/floor will
provide an illustrated indication of the degree of
frame misalignment.
(9) A reference point transferred from one frame
siderail may be 3 mm (1/8 in) ahead or behind the
reference point from the opposite siderail.
(10) Frame bow to the side should not exceed 3
mm per 2,540 mm (1/8 inch per 100 inches) in
length.
(11) The overall width of the frame should not
vary more than 3 mm (1/8 in) from reference point-
to-reference point.
(12) Repeat steps (1) through (11) after straighten-
ing the frame to evaluate the effectiveness.
TWIST AND PARALLEL FRAME MEASUREMENTS
Determine the amount of frame twist and siderail
deviation according to the following procedure.
(1) Mark the vertical measurement reference
points under the frame siderails at 305-mm (12-in)
intervals starting at the rear frame crossmember.
(2) Measure the vertical distance up from a level
surface to each reference point located under the left
and right frame siderails.
(3) The distance to a reference point under one
frame siderail should be 3 mm (1/8 in) greater or less
than the point under the opposite siderail.
(4) Plot the measured vertical distances to scale on
a sheet of graph paper. Plot the distances so that the
frame siderails are located adjacent to each other.
Join the vertical distance points.
13 - 10 FRAME AND BUMPERSJ

Fig. 3 Body HoldDownsÐYJ Vehicles
JFRAME AND BUMPERS 13 - 11

Fig. 4 Frame Alignment DimensionsÐYJ Vehicles
13 - 12 FRAME AND BUMPERSJ

FRAME REPAIR SERVICE
When necessary, conventional vehicle frames that
are bent or twisted can be straightened by applica-
tion of heat. The temperature must not exceed 566ÉC/
1050ÉF.
Damaged frame siderails, crossmembers, and
brackets are repaired either by straightening or by
replacement.
Welded joints between the frame siderails and
crossmembers are not recommended.
FRAME STRAIGHTENING
A straightening repair process should be limited to
frame components that are not severely damaged.
The bolts, nuts and rivets should conform to the spec-
ifications as the original.
FRAME COMPONENT REPLACEMENT
An improperly straightened frame component will
have harmful effects on the overall frame alignment.
FRAME COMPONENT REPAIRS
DRILLING HOLES
Holesshould notbe drilled in frame siderail
flanges because this will severely reduce the frame
strength. Holes drilled in the frame siderail vertical
webs must be 38 mm (1 and 1/2 in) minimum from
the top and bottom flanges.
Newly drilled holes should be located an acceptable
distance away from any existing holes.WELDING
It is recommended that electric welding equipment
be used to weld frame siderails and crossmembers.
A damaged frame component should be closely ex-
amined for hairline cracks. Repair frame component
cracks according to the following procedure.
(1) Drill a hole at each end of the crack with a
3-mm (1/8-in) diameter drill bit.
(2) ``V-groove'' the crack to allow good weld pene-
tration.
(3) Weld the crack.
(4) Grind the weld surface area smooth and install
a reinforcement section at the welded area.
The flanges on reinforcement channel should
be less in width than the siderail flanges. Other-
wise, longitudinal welds are very acceptable.
Complete transverse welds should be avoided.
FRAME REPAIR HARDWARE
Bolts, nuts and rivets can be used to repair frames
or to install a reinforcement section on the frame.
When it is more practical to substitute a bolt for a
rivet, install the next-larger-size diameter bolt to
prevent the bolt from loosening.
Conical-type lockwashers are preferred over the
split-ring type lockwashers. Normally, grade-5 bolts
are adequate for frame repair.Grade-3 bolts (or
less) should not be used.Tightening bolts/nuts
with the correct torque is mandatory to adequately
``lock'' the bolt, lockwasher and nut together, and to
prevent them from loosening.
Fig. 5 Frame Alignment Reference PointsÐTypical
JFRAME AND BUMPERS 13 - 13

YJ BUMPERS AND FRAME ATTACHED COMPONENTS
INDEX
page page
Generator Splash Shield................... 14
Body.................................. 18
Engine Front Support Cushion............... 15
Frame Crossmember Cover................. 14
Front Bumper........................... 14
Fuel and Brake Fluid Tube Retainer Clip....... 16
Fuel Filter Shield and Bracket............... 17
Fuel Tank Skid Plate...................... 16Muffler and Tailpipe Heat Shields............ 17
Muffler/Tailpipe Hanger Bracket.............. 16
Rear Bumper............................ 18
Rear Jounce Bumper..................... 18
Service Information....................... 14
Tow Hooks............................. 14
Transfer Case Skid Plate.................. 15
SERVICE INFORMATION
In some cases, components in the following proce-
dures either support, or are hidden by other compo-
nents.
FRONT BUMPER
The YJ front bumper is a one-piece rail (Fig. 1). A
front crossmember cover (Fig. 1) is also installed on
all YJ vehicles.
BUMPER REMOVAL
(1) Disconnect and remove the fog lamps, if
equipped.
(2) Remove the nuts and bolts that retain the
bumper extensions to the bumper rail and remove
the extensions.
(3) Remove the nuts and bolts that attach the
bumper rail/tow hooks to the frame rails.(4) Remove the bumper rail from the frame rails.
BUMPER INSTALLATION
(1) Position the front bumper on the frame rails.
(2) Install the bolts and attach the front bumper
rail (and tow hooks, if equipped) to the frame rails.
(3) Tighten the bolts to 102 Nzm (75 ft-lbs) torque.
(4) Position the bumper extensions on the bumper
rail and install the retaining bolts.
(5) Tighten the bolts to 104 Nzm (77 ft-lbs) torque.
(6) Install the fog lamps, if equipped.
FRAME CROSSMEMBER COVER
REMOVAL
(1) Remove the screws that attach the crossmem-
ber cover and support to the frame rails.
(2) Remove the crossmember cover and support
from the frame rails.
INSTALLATION
(1) Position the support and crossmember cover on
the frame rails.
(2) Install the attaching screws.
(3) Tighten the screws to 8 Nzm (72 in-lbs) torque.
TOW HOOKS
REMOVAL
(1) Remove the two bolts that attach the tow hook
to the bumper rail and to the frame rail.
(2) Remove the tow hook.
INSTALLATION
(1) Position the tow hook on the bumper rail and
frame rail.
(2) Install the attaching bolts.
(3) Tighten the bolts to 102 Nzm (75 ft-lbs) torque.
GENERATOR SPLASH SHIELD
REMOVAL
(1) Remove the shield retaining nut and washer
(Fig. 2) from the engine oil pan stud (2.5L engines
only).
Fig. 1 Front Bumper Rail, Crossmember Cover &
Tow Hooks
13 - 14 FRAME AND BUMPERSJ

(2) Pry the serrated retainers from the frame rail
holes at each side of the vehicle.
(3) Pry the serrated retainers from the fan shroud
holes (Fig. 2).
(4) Remove the shield from the vehicle.
INSTALLATION
(1) Position the generator splash shield at the fan
shroud and frame rails.
(2) Force the serrated retainers into the fan shroud
holes.
(3) Force the serrated retainers into the frame rail
holes at each side of the vehicle.
ENGINE FRONT SUPPORT CUSHION
REMOVAL
(1) Raise and support the engine.
(2) Remove the nut and bolt that attach the engine
support cushion to the engine support bracket (Figs.
3 and 4).(3) Remove the nut and bolt that attach the sup-
port cushion to the frame adapter bracket.
(4) Remove the support cushion from the frame
adapter bracket.
INSTALLATION
(1) Position the support cushion on the frame
adapter bracket.
(2) Install the bolt and nut that attach the engine
support cushion to the frame adapter bracket.
Tighten the bolt and nut to 49 Nzm (36 ft-lbs) torque.
(3) Install the bolt and nut that attach the engine
support cushion to the engine support bracket.
Tighten the nut to 65 Nzm (48 ft-lbs) torque.
(4) Remove the support and lower the engine.
TRANSFER CASE SKID PLATE
REMOVAL
(1) Raise and support the transmission.
(2) Remove the nuts that attach the transmission
support cushion and torque bracket to the skid plate
(Fig. 5).
(3) Separate the transmission support cushion from
the skid plate.
(4) Remove the nuts and bolts that attach the skid
plate to the frame.
(5) Remove the skid plate from the vehicle.
INSTALLATION
(1) Position the skid plate at the frame and trans-
mission support cushion.
(2) Attach the skid plate to the frame.
(3) Install the nuts that attach the transmission
support cushion and torque bracket to the skid plate.
Tighten the nuts to 56 Nzm (41 ft-lbs) torque.
(4) Remove the support and lower the transmis-
sion.
Fig. 2 Generator Splash Shield
Fig. 3 Engine Support CushionÐ2.5L Engine
Fig. 4 Engine Support CushionÐ4.0L Engine
JFRAME AND BUMPERS 13 - 15

FUEL TANK SKID PLATE
REMOVAL
(1) Position a support under the fuel tank skid
plate.
(2) Remove the nuts that attach the skid plate to
the straps and to the crossmembers (Fig. 6).
(3) Separate the fuel tank strap from the skid
plate.
(4) Support the fuel tank and remove the skid
plate and the pad from the vehicle.
INSTALLATION
(1) Attach the skid plate to the fuel tank strap.
(2) Position and support the pad and skid plate un-
der the fuel tank.
(3) Install the nuts to attach the skid plate to the
straps and to the frame crossmembers. Tighten the
fuel tank strap nuts to 5 Nzm (40 in-lbs) torque.
Tighten the skid plate-to-crossmember nuts with 16
Nzm (138 in-lbs) torque.
(4) Remove the support from under the skid plate.
FUEL AND BRAKE FLUID TUBE RETAINER CLIP
REMOVAL
(1) Remove the fuel/brake fluid tubes from the re-
tainer clip grooves (Fig. 7).
(2) Pry the serrated retainer clip outward and re-
move it from the frame rail hole.
INSTALLATION
(1) Position the serrated retainer clip at the frame
rail hole.
(2) Force the serrated retainer clip inward against
the frame rail.
(3) Insert the fuel/brake fluid tubes in the retainer
clip grooves and press inward to seat them.
MUFFLER/TAILPIPE HANGER BRACKET
REMOVAL
(1) As applicable, detach the muffler or tailpipe
hanger from the insulator (Fig. 8). Remove the insu-
lator from the hanger bracket.
(2) As applicable, remove the nuts and bolts, or
screws that attach the hanger bracket to the frame
rail.
Fig. 5 Transfer Case Skid Plate
Fig. 6 Fuel Tank Skid Plate
Fig. 7 Fuel & Brake Tube Serrated Retainer
ClipsÐTypical
13 - 16 FRAME AND BUMPERSJ

(3) Remove the hanger bracket from the frame
rail.
INSTALLATION
(1) Position the hanger bracket on the frame rail.
(2) As applicable, install the nuts and bolts, or
screws that attach the hanger bracket to the frame
rail. Tighten the nuts/screws securely.
(3) Remove the insulator from the hanger bracket.
(4) As applicable, attach the muffler or tailpipe
hanger to the insulator.
MUFFLER AND TAILPIPE HEAT SHIELDS
REMOVAL
(1) If necessary, remove the muffler and tailpipe
for access.
(2) Remove the retaining screws and the heat
shields from the support bracket (Fig. 9).
INSTALLATION
(1) Position the heat shields on the support bracket
and install screws. Tighten the screws to 5 Nzm (in
44 in-lbs) torque.
(2) If removed, install the muffler and tailpipe.
FUEL FILTER SHIELD AND BRACKET
REMOVAL
(1) Remove the screws that attach the fuel filter
shield to the frame rail (Figs. 10 and 11).
(2) Remove the shield from the frame rail (Fig.
11).
(3) Remove the nut and bolt from the fuel filter
bracket clamp.
(4) Remove the clamp and the fuel filter from the
bracket.
(5) Remove the screws that attach the bracket to
the frame rail.
(6) Remove the bracket from the frame rail.
INSTALLATION
(1) Position the fuel filter bracket on the frame
rail.
Fig. 8 Muffler/Tailpipe Hanger Bracket
Fig. 9 Muffler & Tailpipe Heat Shield
Fig. 10 Fuel Filter Shield & BracketÐInstalled
Fig. 11 Fuel Filter Shield & BracketÐRemoved
JFRAME AND BUMPERS 13 - 17

(2) Install the screws that attach the bracket to
the frame rail. Tighten the screws to 42 Nzm (31 ft-
lbs) torque.
(3) Install the fuel filter in the bracket.
(4) Position the clamp on the bracket and install
bolt and nut. Tighten the nut to 8 Nzm (72 in-lbs)
torque.
(5) Position the fuel filter shield from the frame
rail.
(6) Install the screws that attach the fuel filter
shield to the frame rail. Tighten the screws to 42
Nzm (31 ft-lbs) torque.
REAR JOUNCE BUMPER
REMOVAL
(1) Remove the screws that attach the jounce
bumper to the frame rail (Fig. 12).
(2) Remove the jounce bumper from the frame rail.
INSTALLATION
(1) Position the jounce bumper on the frame rail.
(2) Install the screws that attach the jounce
bumper to the frame rail. Tighten the screws to 20
Nzm (15 ft-lbs) torque.
REAR BUMPER
When equipped with a spare tire carrier attached
to the tailgate, a rear bumperette is attached to the
frame (Figs. 13 and 14).
BUMPERETTE AND DRAW BAR REMOVAL
(1) Remove the bumperette and draw bar retaining
nuts, bolts and washers from the frame rear cross-
member (Figs. 14 and 15).
(2) Remove the bumperettes, spacers, brackets and
draw bar from the rear crossmember.INSTALLATION
(1) Position the spacers, brackets, draw bar and
bumperettes on the rear crossmember.
(2) Install the retaining nuts, bolts and washers in
the frame rear crossmember. Tighten the retaining
nuts and bolts securely.
BODY
REMOVAL
The body is attached to the vehicle frame with
bolts (Fig. 15). The body can be removed for repair,
service access, or replacement, if necessary.
Fig. 12 Rear Jounce Bumpers
Fig. 13 Rear Bumperette
Fig. 14 Rear Bumperette & Draw Bar
13 - 18 FRAME AND BUMPERSJ

Fig. 15 Body Removal/Installation
JFRAME AND BUMPERS 13 - 19