Page 1489 of 2585

SPECIAL TOOLS
EXHAUST SYSTEM
CATALYTIC CONVERTER
DESCRIPTION
The toe board three-way catalytic converter is con-
nected to the exhaust manifold by the use of flex
joint and a gasket. The outlet connects to the muffler
inlet pipe and is secured with a band type clamp
(Fig. 1).
The exhaust flex-joint coupling (Fig. 3) is used to
secure the catalytic converter to the exhaust manifold.
The flex-joint has four bolts, four flag nuts and a gas-
ket that are separate parts from the exhaust flex-joint.
The flex-joint is welded to the catalytic converter.
CAUTION: When servicing, care must be exercised
not to dent or bend the bellows or bellows cover of
the flex-joint. Should this occur, the flex-joint will
eventually fail and require the catalytic converter be
replaced.
OPERATION
The three-way catalytic converter simultaneously
converts three exhaust emissions into harmless
gases. Specifically, HC and CO emissions are con-
verted into water (H2O) and carbon dioxide (CO2).
Oxides of Nitrogen (NOx) are converted into elemen-
tal Nitrogen (N) and water. The three-way catalyst is
most efficient in converting HC, CO and NOx at the
stoichiometric air fuel ratio of 14.7:1.
The oxygen content in a catalyst is important for
efficient conversion of exhaust gases. When a high
oxygen content (lean) air/fuel ratio is present for an
extended period, oxygen content in a catalyst can
reach a maximum. When a rich air/fuel ratio is
present for an extended period, the oxygen content in
the catalyst can become totally depleted. When this
occurs, the catalyst fails to convert the gases. This is
known as catalyst9punch through.9
Catalyst operation is dependent on its ability to
store and release the oxygen needed to complete the
emissions-reducing chemical reactions. As a catalyst
deteriorates, its ability to store oxygen is reduced.
Since the catalyst's ability to store oxygen is some-
what related to proper operation, oxygen storage can
be used as an indicator of catalyst performance.
Refer to the appropriate Diagnostic Information for
diagnosis of a catalyst related Diagnostic Trouble
Code (DTC).
Back Pressure Test Adapter - CH8519
Pressure Transducer CH7063
DRB III & PEP Module - OT-CH6010A
Fig. 3 Flex-joint
1 - FLANGE
2 - END CAPS
3 - CATALYTIC CONVERTER
4 - FLEXIBLE BELLOWS
11 - 4 EXHAUST SYSTEMRS
EXHAUST SYSTEM (Continued)
Page 1490 of 2585

The combustion reaction caused by the catalyst
releases additional heat in the exhaust system, caus-
ing temperature increases in the area of the reactor
under severe operating conditions. Such conditions
can exist when the engine misfires or otherwise does
not operate at peak efficiency.Do notremove spark
plug wires from plugs or by any other means short
out cylinders, if exhaust system is equipped with a
catalytic converter. Failure of the catalytic converter
can occur due to temperature increases caused by
unburned fuel passing through the converter. This
deterioration of the catalyst core can result in exces-
sively high emission levels, noise complaints, and
exhaust restrictions.
Unleaded gasoline must be used to avoid ruining
the catalyst core. Do not allow engine to operate
above 1200 RPM in neutral for extended periods over
5 minutes. This condition may result in excessive
exhaust system/floor pan temperatures because of no
air movement under the vehicle.
The flex joint allows flexing as the engine moves,
preventing breakage that could occur from the back-
and-forth motion of a transverse mounted engine.
CAUTION: Due to exterior physical similarities of
some catalytic converters with pipe assemblies,
extreme care should be taken with replacement
parts. There are internal converter differences
required in some parts of the country (particularly
vehicles built for States with strict emission
requirements) and between model years.
REMOVAL
(1) Loosen clamp and disconnect the muffler/reso-
nator assembly from catalytic converter pipe.
(2) Disconnect downstream oxygen sensor electri-
cal connector (Fig. 4). For removal of downstream
oxygen sensor, (Refer to 14 - FUEL SYSTEM/FUEL
INJECTION/O2 SENSOR - REMOVAL).
(3) Remove catalytic converter to exhaust manifold
attaching fasteners (Fig. 5).
(4) Remove catalytic converter and gasket (Fig. 5).
INSPECTION
WARNING: THE NORMAL OPERATING TEMPERA-
TURE OF THE EXHAUST SYSTEM IS VERY HIGH.
THEREFORE, NEVER ATTEMPT TO SERVICE ANY
PART OF THE EXHAUST SYSTEM UNTIL IT IS
COOLED. SPECIAL CARE SHOULD BE TAKEN
WHEN WORKING NEAR THE CATALYTIC CON-
VERTER. THE TEMPERATURE OF THE CONVERTER
RISES TO A HIGH LEVEL AFTER A SHORT PERIOD
OF ENGINE OPERATION TIME.Check catalytic converter for a flow restriction.
(Refer to 11 - EXHAUST SYSTEM - DIAGNOSIS
AND TESTING) Exhaust System Restriction Check
for procedure.
Fig. 4 Downstream Oxygen Sensor
1 - OXYGEN SENSOR CONNECTOR
2 - CATALYTIC CONVERTER
3 - DOWNSTREAM OXYGEN SENSOR
4 - ENGINE HARNESS CONNECTOR
Fig. 5 Catalytic Converter to Exhaust Manifold
1 - FLAG NUT
2 - GASKET
3 - BOLT
4 - CATALYTIC CONVERTER
RSEXHAUST SYSTEM11-5
CATALYTIC CONVERTER (Continued)
Page 1491 of 2585

Visually inspect the catalytic converter element by
using a borescope or equivalent. Remove oxygen sen-
sor(s) and insert borescope. If borescope is not avail-
able, remove converter and inspect element using a
flashlight. Inspect element for cracked or melted sub-
strate.
NOTE: Before replacing a catalytic converter, deter-
mine the root cause of failure. Most catalytic con-
verter failures are caused by air, fuel or ignition
problems. (Refer to Appropriate Diagnostic Informa-
tion) for test procedures.
INSTALLATION
(1) Position new gasket onto the manifold flange
and install catalytic converter (Fig. 5). Tighten fas-
teners to 37 N´m (325 in. lbs.).
NOTE: Be careful not to twist or kink the oxygen
sensor wires.
(2) Install (if removed) and connect the down-
stream oxygen sensor (Fig. 4).
(3) Install the muffler/resonator assembly. (Refer
to 11 - EXHAUST SYSTEM/MUFFLER - INSTALLA-
TION)
CROSS-OVER PIPE - 3.3/3.8L
REMOVAL
(1) Disconnect negative cable from battery.
(2) Remove the fasteners attaching the left bank
manifold connection to cross-over pipe (Fig. 6).
(3) Raise vehicle and remove the left front wheel.
(4) Access the lower right bank pipe connection
fastener through the left front wheel opening using a
long ratchet extension. Loosen and remove the lower
fastener.
(5) Remove the upper right bank pipe connection
fastener by accessing though the catalytic converter
floor pan tunnel.
(6) Lower the vehicle.
(7) Remove the cross-over pipe (Fig. 6).
(8) Remove gaskets and discard (Fig. 6).
INSTALLATION
(1) Position cross-over pipe to the manifold connec-
tions (Fig. 6).
(2) Position new gasket on left bank (front) pipe
connection and loosely install fasteners (Fig. 6).
(3) Raise the vehicle.
(4) Position new gasket on the right bank pipe con-
nection and install fasteners.
(5) Tighten right bank upper fastener to 41 N´m
(30 ft. lbs.).(6) Tighten right bank lower fastener to 41 N´m
(30 ft. lbs.) using a long ratchet extension accessing
through the left wheel opening.
(7) Install the left front wheel and lower vehicle.
(8) Tighten the left bank pipe connection fasteners
to 41 N´m (30 ft. lbs.) (Fig. 6).
HEAT SHIELDS
DESCRIPTION
The exhaust system heat shields (Fig. 7), (Fig. 8),
or (Fig. 9) are attached to the under body of the vehi-
cle. On vehicles equipped with All Wheel Dive
(AWD), an additional heat shield is mounted to the
catalytic converter.
Fig. 6 CROSS-OVER PIPE
1 - CROSS-OVER PIPE
2 - BOLT
3 - GASKET
4 - FLAG NUT
Fig. 7 CATALYTIC CONVERTER HEAT SHIELD
1 - HEAT SHIELD - CATALYTIC CONVERTER
2 - SCREW (QTY. 4)
11 - 6 EXHAUST SYSTEMRS
CATALYTIC CONVERTER (Continued)
Page 1492 of 2585

OPERATION
Heat shields are needed to protect both the vehicle
and the environment from the high temperatures
developed near the catalytic converter.
Avoid application of rust prevention com-
pounds or undercoating materials to exhaust
system floor pan heat shields on cars so
equipped. Light over spray near the edges is
permitted. Application of coating will greatly
reduce the efficiency of the heat shields result-
ing in excessive floor pan temperatures and
objectionable fumes.
REMOVAL
(1) Raise vehicle on hoist.
(2) Remove fasteners attaching applicable heat
shield (Fig. 7), (Fig. 8), or (Fig. 9).
(3) Remove heat shield(s).
INSTALLATION
(1) Position heat shield(s) to underbody.
(2) Install heat shield fasteners and tighten to 2.6
N´m (23 in. lbs.) (Fig. 7), (Fig. 8), or (Fig. 9).
(3) Lower vehicle.
MUFFLER
REMOVAL
(1) Raise vehicle on a body contact type hoist.
NOTE: To provide removal clearance between muf-
fler/resonator pipe and rear axle parts, the rear sus-
pension must be relieved of all body weight.
(2) Apply a penetrating oil to clamp nuts of com-
ponent requiring removal.
CAUTION: When servicing the exhaust system, care
must be exercised not to dent or bend the bellows
of the flex-joint. Should this occur, the flex-joint will
eventually fail, requiring replacement of the cata-
lytic converter.
(3) Disconnect the right side axle half shaft from
the rear differential module (AWD equipped only).
(4) Loosen the band clamp (Fig. 10) at the muffler
to converter pipe connection.
(5) Remove the exhaust hangers to body screws
(Fig. 10).
(6) Separate muffler pipe from converter pipe.
(7) Remove muffler/resonator assembly by moving
assembly forward and guiding the resonator through
the rear axle to body opening.
(8) Clean ends of pipes or muffler to assure mat-
ing of all parts. Discard broken or worn insulators,
rusted clamps, supports and attaching parts.When
replacement is required on any component of
the exhaust system, it is important that original
equipment parts (or equivalent) be used for the
following conditions:
²Ensure proper alignment with other components
in the system.
²Provide acceptable exhaust noise levels.
²Provide proper exhaust system back pressure for
maintaining emission and performance levels.
INSTALLATION
(1) Install the muffler/resonator assembly by guid-
ing resonator between the rear axle and body.
(2) Connect the muffler pipe to the converter pipe
but do not tighten band clamp (Fig. 10).
(3) Position hangers to body and install screws
starting at the resonator working forward (Fig. 10).
Tighten hanger screws to 28 N´m (250 in. lbs.).
Fig. 8 MUFFLER HEAT SHIELD
1 - HEAT SHIELD - MUFFLER
2 - SCREW (QTY. 6)
Fig. 9 RESONATOR PIPE HEAT SHIELD
1 - SCREW (QTY. 3)
2 - HEAT SHIELD - RESONATOR PIPE
3 - MUFFLER
RSEXHAUST SYSTEM11-7
HEAT SHIELDS (Continued)
Page 1493 of 2585

(4) Insert muffler pipe into catalytic converter pipe
until the hangers are positioned as shown in (Fig. 11)
CAUTION: Band clamps should never be tightened
such that the two sides of the clamps are bottomed
out against the center hourglass shaped centerblock. Once this occurs, the clamp band has been
stretched and has lost its clamping force and must
be replaced.
To replace the band clamp; remove the nut and peel
back the ends of the clamp until spot weld breaks.
Clean remaining spot weld from the pipe using a
file or grinder until surface is smooth.
NOTE: Maintain proper clamp orientation when
replacing with new clamp.
(5) Tighten the band clamp to 55 N´m (40 ft. lbs.)
(Fig. 12).
(6) Connect the right side half shaft to the rear
differential module (AWD equipped only).
Fig. 10 Exhaust System - Typical (All Vehicles)
1 - SCREW - RESONATOR HANGER TO BODY 3 - MUFFLER & RESONATOR ASSEMBLY
2 - SCREW - MUFFLER HANGER TO BODY 4 - CATALYTIC CONVERTER PIPE
Fig. 11 Exhaust System Alignment
1 - HANGER BRACKET TO BODY
2 - ISOLATOR
3 - HANGER - MUFFLER/RESONATOR SUPPORT
4-6mm(0.25 in.)
Fig. 12 Band Clamp
1 - BAND CLAMP
2 - TORQUE SPECIFICATION
11 - 8 EXHAUST SYSTEMRS
MUFFLER (Continued)
Page 1494 of 2585
RESONATOR
REMOVAL
(1) (Refer to 11 - EXHAUST SYSTEM/MUFFLER -
REMOVAL)
INSTALLATION
(1) (Refer to 11 - EXHAUST SYSTEM/MUFFLER -
INSTALLATION)
RSEXHAUST SYSTEM11-9
Page 1495 of 2585
Page 1496 of 2585

FRAME & BUMPERS
TABLE OF CONTENTS
page page
BUMPERS
SPECIFICATIONS - TORQUE...............1
FRONT FASCIA
REMOVAL.............................1
INSTALLATION..........................1
FRONT BUMPER REINFORCEMENT
REMOVAL.............................2
INSTALLATION..........................2
REAR FASCIA
REMOVAL.............................2
INSTALLATION..........................2
REAR BUMPER REINFORCEMENT
REMOVAL.............................3
INSTALLATION..........................3
REAR FASCIA - SCUFF PAD
REMOVAL.............................3INSTALLATION..........................4
FRAME
SPECIFICATIONS
FRAME DIMENSIONS...................4
SPECIFICATIONS - TORQUE.............9
FRONT CRADLE CROSSMEMBER
DESCRIPTION
DESCRIPTION - FRONT CRADLE
CROSSMEMBER.......................9
DESCRIPTION - FRONT CRADLE
CROSSMEMBER THREAD REPAIR.........9
REMOVAL.............................10
INSTALLATION.........................11
FRONT CROSSMEMBER MOUNT BUSHINGS
REMOVAL.............................12
INSTALLATION.........................12
BUMPERS
SPECIFICATIONS - TORQUE
DESCRIPTION N´m Ft. Lbs. In. Lbs.
Front bumper reinforcement attaching nut 54 40 Ð
Rear bumper reinforcement attaching nut 27 20 Ð
FRONT FASCIA
REMOVAL
(1) Release hood latch and open hood.
(2) Remove the headlamp assemblies (Refer to 8 -
ELECTRICAL/LAMPS/LIGHTING - EXTERIOR/
HEADLAMP - REMOVAL).
(3) Hoist vehicle and support with safety stands.
(4) Remove the five bolts attaching bottom of fas-
cia/air dam to radiator closure panel.
(5) Remove front wheels.
(6) Remove front wheelhouse splash shields fasten-
ers as necessary to gain access to bolts attaching
front fascia to fender. (Refer to 23 - BODY/EXTERI-
OR/ WHEELHOUSE SPLASH SHIELD -
REMOVAL).
(7) Remove the two bolts and two nuts attaching
fascia to the front fenders (Fig. 1).
(8) Disconnect fog lamp wire connectors, if neces-
sary.
(9) Lower vehicle.(10) Remove two bolts attaching the upper grille
support to the headlamp mounting panel at each side
of the grille.
(11) Remove bumper fascia from vehicle.
INSTALLATION
(1) Position front bumper fascia on vehicle.
(2) Install the two bolts attaching fascia to head-
lamp mounting panel at each side of grille.
(3) Hoist vehicle and support with safety stands.
(4) Install the two bolts and two nuts attaching
fascia to the front fenders (Fig. 1). The fascia should
be flush to fender.
(5) Install front wheelhouse splash shields fasten-
ers. (Refer to 23 - BODY/EXTERIOR/ WHEEL-
HOUSE SPLASH SHIELD - INSTALLATION).
(6) Install front wheels.
(7) Connect fog lamp wire connectors, if necessary.
(8) Install the five bolts attaching bottom of fascia
to radiator closure panel.
(9) Lower the vehicle.
RSFRAME & BUMPERS13-1