Bolts JEEP GRAND CHEROKEE 2003 WJ / 2.G Workshop Manual

body. Install Special Tool 8514 lock pin into hole on
front of tensioner. Slowly open vise to transfer piston
spring force to lock pin (Fig. 128).
(2) Position primary chain tensioner over oil pump
and insert bolts into lower two holes on tensioner
bracket. Tighten bolts to 28 N´m (250 in. lbs.).
CAUTION: Overtightening the tensioner arm torxT
bolt can cause severe damage to the cylinder head.
Tighten torxTbolt to specified torque only.
(3) Install right side chain tensioner arm. Apply
MopartLock N, Seal to torxtbolt, tighten bolt to 17
N´m (150 in. lbs.).
NOTE: The silver bolts retain the guides to the cyl-
inder heads and the black bolts retain the guides to
the engine block.(4) Install the left side chain guide. Tighten the
bolts to 28 N´m (250 in. lbs.).
CAUTION: Overtightening the tensioner arm torxT
bolt can cause severe damage to the cylinder head.
Tighten torxTbolt to specified torque only.
(5) Install left side chain tensioner arm. Apply
MopartLock N, Seal to torxtbolt, tighten bolt to 17
N´m (150 in. lbs.).
(6) Install the right side chain guide. Tighten the
bolts to 28 N´m (250 in. lbs.).
(7) Install both secondary chains onto the idler
sprocket. Align two plated links on the secondary
chains to be visible through the two lower openings
on the idler sprocket (4 o'clock and 8 o'clock). Once
the secondary timing chains are installed, position
special tool 8515 to hold chains in place for installa-
tion (Fig. 129).
Fig. 127 Timing Chain System
1 - RIGHT CAMSHAFT SPROCKET AND SECONDARY CHAIN
2 - SECONDARY TIMING CHAIN TENSIONER (LEFT AND RIGHT
SIDE NOT COMMON)
3 - SECONDARY TENSIONER ARM
4 - LEFT CAMSHAFT SPROCKET AND SECONDARY CHAIN
5 - CHAIN GUIDE
6 - TWO PLATED LINKS ON RIGHT CAMSHAFT CHAIN7 - PRIMARY CHAIN
8 - IDLER SPROCKET
9 - CRANKSHAFT SPROCKET
10 - PRIMARY CHAIN TENSIONER
11 - TWO PLATED LINKS ON LEFT CAMSHAFT CHAIN
12 - SECONDARY TENSIONER ARM
9 - 150 ENGINE - 4.7LWJ
TIMING BELT/CHAIN AND SPROCKETS (Continued)

(13) Remove Special Tool 8515, then attach both
sprockets to camshafts. Remove excess oil from bolts,
then Install sprocket bolts, but do not tighten at this
time.
(14) Verify that all plated links are aligned with
the marks on all sprockets and the ªV8º marks on
camshaft sprockets are at the 12 o'clock position (Fig.
127).
CAUTION: Ensure the plate between the left sec-
ondary chain tensioner and block is correctly
installed.
(15) Install both secondary chain tensioners.
Tighten bolts to 28 N´m (250 in. lbs.).
NOTE: Left and right secondary chain tensioners
are not common.
(16) Before installing idler sprocket bolt, lubricate
washer with oil, and tighten idler sprocket assembly
retaining bolt to 34 N´m (25 ft. lbs.).
(17) Remove all locking pins (3) from tensioners.
CAUTION: After pulling locking pins out of each
tensioner, DO NOT manually extend the tensioner(s)
ratchet. Doing so will over tension the chains,
resulting in noise and/or high timing chain loads.
(18) Using Special Tool 6958, Spanner with Adap-
tor Pins 8346, tighten left (Fig. 131) and right (Fig.
132). camshaft sprocket bolts to 122 N´m (90 ft. lbs.).
(19) Rotate engine two full revolutions. Verify tim-
ing marks are at the follow locations:
²primary chain idler sprocket dot is at 12 o'clock
(Fig. 127)
²primary chain crankshaft sprocket dot is at 6
o'clock (Fig. 127)
²secondary chain camshaft sprockets ªV8º marks
are at 12 o'clock (Fig. 127)(20) Lubricate all three chains with engine oil.
(21) After installing all chains, it is recommended
that the idler gear end play be checked (Fig. 133).
The end play must be within 0.10±0.25 mm (0.004±
0.010 in.). If not within specification, the idler gear
must be replaced.
Fig. 131 Tightening Left Side Camshaft Sprocket
Bolt
1 - TORQUE WRENCH
2 - CAMSHAFT SPROCKET
3 - LEFT CYLINDER HEAD
4 - SPECIAL TOOL 6958 SPANNER WITH ADAPTER PINS 8346
9 - 152 ENGINE - 4.7LWJ
TIMING BELT/CHAIN AND SPROCKETS (Continued)

DIAGNOSIS AND TESTING - EXHAUST SYSTEM
EXHAUST SYSTEM DIAGNOSIS CHART
CONDITION POSSIBLE CAUSE CORRECTION
EXCESSIVE EXHAUST NOISE1. Leaks at pipe joints. 1. Tighten clamps to specified
torque at leaking joints (Refer to 11
- EXHAUST SYSTEM -
SPECIFICATIONS).
2. Burned or blown out muffler. 2. Replace muffler assembly (Refer
to 11 - EXHAUST SYSTEM/
MUFFLER - REMOVAL). Check
exhaust system.
3. Burned or rusted-out exhaust
pipe.3. Replace exhaust pipe (Refer to
11 - EXHAUST SYSTEM/EXHAUST
PIPE - REMOVAL).
4. Exhaust pipe leaking at manifold
flange.4. Tighten connection attaching nuts
(Refer to 11 - EXHAUST SYSTEM -
SPECIFICATIONS).
5. Exhaust manifold cracked or
broken.5. Replace exhaust manifold (Refer
to 9 - ENGINE/MANIFOLDS/
EXHAUST MANIFOLD -
REMOVAL).
6. Leak between exhaust manifold
and cylinder head.6. Tighten exhaust manifold to
cylinder head stud nuts or bolts
(Refer to 9 - ENGINE -
SPECIFICATIONS).
7. Restriction in muffler or tailpipe. 7. Remove restriction, if possible.
Replace muffler or tailpipe, as
necessary.
8. Exhaust system contacting body
or chassis.8. Re-align exhaust system to clear
surrounding components.
LEAKING EXHAUST GASES1. Leaks at pipe joints. 1. Tighten/replace clamps at leaking
joints (Refer to 11 - EXHAUST
SYSTEM - SPECIFICATIONS).
SPECIFICATIONS
TORQUE
DESCRIPTION N´m Ft. In.
Lbs. Lbs.
Catalytic Converter-to-
Exhaust PipeÐNuts28 Ð 250
Exhaust Pipe-to-ManifoldÐ
Nuts31 23 Ð
Heat Shield RetainingÐ
Nuts2.0 Ð 20DESCRIPTION N´m Ft. In.
Lbs. Lbs.
Muffler-to-Catalytic
Converter
U-bolt clamp 47 35 Ð
Rear Tailpipe HangerÐ
Bolts22 Ð 192
WJEXHAUST SYSTEM 11 - 3
EXHAUST SYSTEM (Continued)

(1) Raise and support the vehicle.
(2) Saturate the bolts and nuts with heat valve
lubricant. Allow 5 minutes for penetration.
(3) Remove nuts from the catalytic converter and
exhaust pipe flange connection (Fig. 4).
(4) Loosen exhaust clamp from the catalytic con-
verter and muffler connection (Fig. 4).
(5) Disconnect oxygen sensor wiring (Fig. 4).
(6) Heat the catalytic converter to muffler connec-
tion with a torch until the metal becomes cherry red.
(7) While the metal is still cherry red, twist the
catalytic converter back and forth to separate it from
the exhaust pipe and the muffler (Fig. 5).
INSPECTION
Look at the stainless steel body of the converter,
inspect for bulging or other distortion that could be a
result of overheating. If the converter has a heat
shield attached make sure it is not bent or loose.If you suspect internal damage to the catalyst, tap-
ping the bottom of the catalyst with a rubber mallet
may indicate a damaged core.
INSTALLATION
(1) Position the catalytic converter onto the
exhaust pipe flange connection (Fig. 4). Tighten the
nuts to 28 N´m (250 in. lbs.) torque.
(2) Install the muffler onto the catalytic converter
until the alignment tab is inserted into the align-
ment slot.
(3) Install the exhaust clamp at the muffler and
catalytic converter connection (Fig. 4). Tighten the
clamp nuts to 47 N´m (35 ft. lbs.) torque.
(4) Connect oxygen sensor wiring (Fig. 4).
(5) Lower the vehicle.
(6) Start the engine and inspect for exhaust leaks
and exhaust system contact with the body panels.
Adjust the alignment, if needed.
Fig. 4 Exhaust Pipe-to-Catalytic Converter-to-Muffler
Connection
1 - EXHAUST CLAMP ASSEMBLY
2 - OXYGEN SENSOR
3 - MUFFLER
4 - CATALYTIC CONVERTER
5 - EXHAUST PIPE WITH FLANGE JOINT
6 - NUTS (3)
Fig. 5 Catalytic ConverterÐRemoval
1 - EXHAUST PIPE WITH FLANGE
2 - NUTS (3)
3 - CATALYTIC CONVERTER
WJEXHAUST SYSTEM 11 - 5
CATALYTIC CONVERTER - 4.0L (Continued)

(1) Raise and support the vehicle.
(2) Saturate the bolts and nuts with heat valve
lubricant. Allow 5 minutes for penetration.
(3) Remove nuts from the catalytic converter and
exhaust pipe flange connection (Fig. 7).
(4) Loosen exhaust clamp from the catalytic con-
verter and muffler connection (Fig. 7).
(5) Disconnect oxygen sensor wiring (Fig. 7).
(6) Heat the catalytic converter to muffler connec-
tion with a torch until the metal becomes cherry red.
(7) While the metal is still cherry red, twist the
catalytic converter back and forth to separate it from
the muffler (Fig. 8).
INSPECTION
Look at the stainless steel body of the converter,
inspect for bulging or other distortion that could be a
result of overheating. If the converter has a heat
shield attached make sure it is not bent or loose.
If you suspect internal damage to the catalyst, tap-
ping the bottom of the catalyst with a rubber mallet
may indicate a damaged core.
INSTALLATION
(1) Position the catalytic converter onto the
exhaust pipe flange connection (Fig. 7). Tighten the
nuts to 28 N´m (250 in. lbs.) torque.
(2) Install the muffler onto the catalytic converter
until the alignment tab is inserted into the align-
ment slot.
(3) Install the exhaust clamp at the muffler and
catalytic converter connection (Fig. 7). Tighten the
clamp nuts to 47 N´m (35 ft. lbs.) torque.
(4) Connect oxygen sensor wiring (Fig. 7).
(5) Lower the vehicle.
(6) Start the engine and inspect for exhaust leaks
and exhaust system contact with the body panels.
Adjust the alignment, if needed.
Fig. 7 Exhaust Pipe-to-Catalytic Converter-to-Muffler
Connection
1 - EXHAUST CLAMP ASSEMBLY
2 - OXYGEN SENSOR
3 - MUFFLER
4 - CATALYTIC CONVERTER
5 - EXHAUST PIPE WITH FLANGE JOINT
6 - NUTS (3)
Fig. 8 Catalytic ConverterÐRemoval
1 - EXHAUST PIPE WITH FLANGE
2 - NUTS (3)
3 - CATALYTIC CONVERTER
WJEXHAUST SYSTEM 11 - 7
CATALYTIC CONVERTER - 4.7L (Continued)

EXHAUST PIPE - 4.0L
REMOVAL
WARNING: IF TORCHES ARE USED WHEN WORK-
ING ON THE EXHAUST SYSTEM, DO NOT ALLOW
THE FLAME NEAR THE FUEL LINES.
WARNING: THE NORMAL OPERATING TEMPERA-
TURE OF THE EXHAUST SYSTEM IS VERY HIGH.
THEREFORE, NEVER WORK AROUND OR ATTEMPT
TO SERVICE ANY PART OF THE EXHAUST SYSTEM
UNTIL IT IS COOLED. SPECIAL CARE SHOULD BE
TAKEN WHEN WORKING NEAR THE CATALYTIC
CONVERTER. THE TEMPERATURE OF THE CON-
VERTER RISES TO A HIGH LEVEL AFTER A SHORT
PERIOD OF ENGINE OPERATION TIME.
(1) Raise and support the vehicle.(2) Saturate the bolts and nuts with heat valve
lubricant. Allow 5 minutes for penetration.
(3) Remove the oxygen sensor from the exhaust
pipe (Fig. 9).
(4) Remove the nuts from the exhaust pipe to cat-
alytic converter flange connection (Fig. 10).
(5) Disconnect the exhaust pipe from the exhaust
manifold (Fig. 11).
INSPECTION
Discard rusted clamps, broken or worn supports
and attaching parts. Replace a component with orig-
inal equipment parts, or equivalent. This will assure
proper alignment with other parts in the system and
provide acceptable exhaust noise levels.
INSTALLATION
(1) Connect the exhaust pipe to the engine exhaust
manifold. Tighten the nuts to 31 N´m (23 ft. lbs.)
(Fig. 11).
Fig. 9 O2 Sensor Location 4.0L
11 - 8 EXHAUST SYSTEMWJ

EXHAUST PIPE - 4.7L
REMOVAL
WARNING: IF TORCHES ARE USED WHEN WORK-
ING ON THE EXHAUST SYSTEM, DO NOT ALLOW
THE FLAME NEAR THE FUEL LINES.
WARNING: THE NORMAL OPERATING TEMPERA-
TURE OF THE EXHAUST SYSTEM IS VERY HIGH.
THEREFORE, NEVER WORK AROUND OR ATTEMPT
TO SERVICE ANY PART OF THE EXHAUST SYSTEM
UNTIL IT IS COOLED. SPECIAL CARE SHOULD BE
TAKEN WHEN WORKING NEAR THE CATALYTIC
CONVERTER. THE TEMPERATURE OF THE CON-
VERTER RISES TO A HIGH LEVEL AFTER A SHORT
PERIOD OF ENGINE OPERATION TIME.
(1) Raise and support the vehicle.(2) Saturate the bolts and nuts with heat valve
lubricant. Allow 5 minutes for penetration.
(3) Remove the oxygen sensor from the exhaust
pipe (Fig. 13).
(4) Remove the retaining nuts holding catalytic
converter to exhaust pipe (Fig. 14).
(5) Disconnect the exhaust pipe from the exhaust
manifold. (Fig. 15)
INSPECTION
Discard rusted clamps, broken or worn supports
and attaching parts. Replace a component with orig-
inal equipment parts, or equivalent. This will assure
proper alignment with other parts in the system and
provide acceptable exhaust noise levels.
INSTALLATION
(1) Connect the exhaust pipe to the engine exhaust
manifold. Tighten the nuts (A) to 31 N´m (23 ft. lbs.)
(Fig. 15).
Fig. 13 4.7L Catalytic Converter and O2 Sensor Configuration - 50 State Emissions
11 - 10 EXHAUST SYSTEMWJ

NOTE: When servicing the exhaust system, replace
the factory installed uni-clamp with standard u-bolt
clamps.
(2) Position the catalytic converter onto the
exhaust pipe flange connection. Tighten retaining
nuts to 28 N´m (250 in. lbs.). (Fig. 16)
(3) Coat the oxygen sensor with anti-seize com-
pound. Install the sensor and tighten the nut to 48
N´m (35 ft. lbs.) torque (Fig. 13).
(4) Lower the vehicle.
(5) Start the engine and inspect for exhaust leaks
and exhaust system contact with the body panels.
Adjust the alignment, if needed.
(6) After initial start-up, check the engine exhaust
manifold to exhaust pipe nuts for proper torque.
Fig. 14 Catalytic ConverterÐRemoval
1 - EXHAUST PIPE WITH FLANGE
2 - NUTS (3)
3 - CATALYTIC CONVERTER
Fig. 15 Exhaust Pipe 4.7L
1 - EXHAUST PIPE HANGER
A - NUTS (4)
3 - EXHAUST PIPE
B - BOLTS (4)
Fig. 16 Installing Exhaust Clamps
1 - CATALYTIC CONVERTER
2 - MUFFLER
WJEXHAUST SYSTEM 11 - 11
EXHAUST PIPE - 4.7L (Continued)

HEAT SHIELDS
DESCRIPTION
Heat shields are needed to protect both the vehicle
and the environment from the high temperatures
developed by the catalytic converter. The catalytic
converter releases additional heat into the exhaust
system. Under severe operating conditions, the tem-
perature increases in the area of the converter. Such
conditions can exist when the engine misfires or oth-
erwise does not operate at peak efficiency (Fig. 17).
MUFFLER
DESCRIPTION
Both the 4.0L and 4.7L engines use a stainless
steel muffler to control exhaust noise levels and
exhaust back pressure. The muffler and tailpipe are
a one piece assembly (Fig. 18).
REMOVAL
All original equipment exhaust systems are manu-
factured with the tailpipe welded to the muffler. Ser-
vice replacement mufflers and tailpipes are either
clamped together or welded together.
WARNING: IF TORCHES ARE USED WHEN WORK-
ING ON THE EXHAUST SYSTEM, DO NOT ALLOW
THE FLAME NEAR THE FUEL LINES.
(1) Raise and support the vehicle.
(2) Saturate the bolts and nuts with heat valve
lubricant. Allow 5 minutes for penetration.(3) Loosen the exhaust clamp on the catalytic con-
verter to muffler connection (Fig. 19).
(4) Heat the catalytic converter-to-muffler connec-
tion with a torch until the metal becomes cherry red.
(5) While the metal is still cherry red, remove the
tailpipe/muffler assembly from the catalytic con-
verter.
(6) Remove the tailpipe from the tailpipe hanger
(Fig. 20).
(7) Remove the tailpipe/muffler assembly (Fig. 20).
INSTALLATION
(1) If the tailpipe hanger assembly was removed,
install the hanger to the frame. Tighten the bolts to
22 N´m (192 in. lbs.) torque.
(2) Position the tailpipe and muffler onto the
tailpipe hanger (Fig. 20) .
(3) Install the muffler onto the catalytic converter.
Make sure that the tailpipe has sufficient clearance
from the floor pan. Install exhaust clamp and tighten
the nuts to 47 N´m (35 ft. lbs.) torque (Fig. 19) .
(4) Lower the vehicle.
(5) Start the engine and inspect for exhaust leaks
and exhaust system contact with the body panels.
Adjust the alignment, if needed.
Fig. 17 Front and Rear Floor Pan Heat Shields
Typical
1 - REAR FLOOR PAN HEAT SHIELD
2 - HEAT SHIELD RETAINING NUTS (QTY 8)
3 - FRONT FLOOR PAN HEAT SHIELD
Fig. 18 Muffler and Tailpipe
1 - CATALYTIC CONVERTER
2 - TAILPIPE HANGER
3 - TAILPIPE
4 - MUFFLER
11 - 12 EXHAUST SYSTEMWJ

FRAME & BUMPERS
TABLE OF CONTENTS
page page
FRONT ABSORBER
REMOVAL.............................1
INSTALLATION..........................1
FRONT FASCIA
REMOVAL.............................1
INSTALLATION..........................1
REAR ABSORBER
REMOVAL.............................2
INSTALLATION..........................2
REAR FASCIA
REMOVAL.............................2
INSTALLATION..........................4
FRAME
SPECIFICATIONS
SPECIFICATIONS - TORQUE.............4
FRAME DIMENSIONS...................4
FRONT SKID PLATE
REMOVAL.............................7INSTALLATION..........................7
FRONT TOW HOOK
REMOVAL.............................7
INSTALLATION..........................7
FUEL TANK SKID PLATE
DESCRIPTION..........................7
REAR TOW HOOK
REMOVAL.............................7
INSTALLATION..........................7
TRAILER HITCH
REMOVAL.............................8
INSTALLATION..........................8
TRANSFER CASE SKID PLATE
REMOVAL.............................8
INSTALLATION..........................8
FRONT ABSORBER
REMOVAL
(1) Remove front fascia, refer to (Refer to 13 -
FRAMES & BUMPERS/BUMPERS/FRONT FASCIA
- REMOVAL).
(2) Remove the retainer attaching the absorber to
the fascia.
(3) Separate the absorber from the fascia.
INSTALLATION
(1) Position the absorber on the fascia.
(2) Install the retainer attaching the absorber to
the fascia.
(3) Install front fascia. Refer to (Refer to 13 -
FRAMES & BUMPERS/BUMPERS/FRONT FASCIA
- INSTALLATION).
FRONT FASCIA
REMOVAL
(1) Raise and support vehicle.
(2) Turn front wheels to access rivets and remove
plastic rivets attaching fascia to wheel liner.
(3) Remove bolts attaching fascia to fender (Fig. 1).(4) Remove plastic push pin fasteners attaching
front fascia to lower radiator crossmember splash
shield (Fig. 2).
(5) Disengage fog lamp connectors, if equipped.
(6) Remove screws attaching fascia/grille to upper
radiator crossmember (Fig. 3).
(7) Slide fascia forward to separate from vehicle.
INSTALLATION
(1) Slide fascia onto vehicle engaging fascia with
tabs on bottom of front fenders.
(2) Install screws attaching fascia/grille to upper
radiator crossmember (Fig. 3).
(3) Install bolts attaching fascia to fender (Fig. 1).
(4) Engage fog lamp connectors, if equipped.
(5) Install plastic rivets attaching fascia to wheel
liner.
(6) Install plastic push pin fasteners attaching
front fascia to lower radiator crossmember splash
shield (Fig. 2).
(7) Remove supports and lower vehicle.
WJFRAME & BUMPERS 13 - 1