
CONVERTER-CATALYTIC
DESCRIPTION
WARNING: THE NORMAL OPERATING TEMPERATURE OF THE EXHAUST SYSTEM IS VERY HIGH. THERE-
FORE, NEVER WORK AROUND OR ATTEMPT TO SERVICE ANY PART OF THE EXHAUST SYSTEMUNTIL IT
IS COOLED. SPECIAL CARE SHOULD BE TAKEN WHEN WORKING NEAR THE CATALYTIC CONVERTER.
THE TEMPERATURE OF THE CONVERTER RISES TO A HIGH LEVEL AFTER A SHORT PERIOD OFENGINE
OPERATION TIME.
CAUTION: DO NOT remove spark plug wires from plugs or by any other means short out cylinders. Failure
of the catalytic converter can occur due to a temperature increase caused by unburned fuel passing
through the converter.
The stainless steel catalytic converter body is designed to last the life of the vehicle. Excessive heat can result in
bulging or other distortion, but excessive heat will not be the fault of theconverter. If unburned fuel enters the con-
verter, overheating may occur. If a converter is heat-damaged, correct the cause of the damage at the same time
the converter is replaced. Also, inspect all other components of the exhaust system for heat damage.
Unleaded gasoline must be used to avoid contaminating the catalyst core.
50 State emission vehicles incorporate two mini catalytic converters located after the exhaust manifolds and before
the inline catalytic converter.
OPERATION
The catalytic converter captures and burns any unburned fuel mixture exiting the combustion chambers during the
exhaust stroke of the engine. This process aids in reducing emissions output.
REMOVAL
3.7L/4.7L ENGINE
1. Raise and support vehicle.
2. Saturate the bolts and nuts with heat valve lubri-
cant. Allow 5 minutes for penetration.
3. Disconnect oxygen sensor electrical connectors.
4. Remove clamp (4).
5. Remove bolts exhaust to manifold (2).
6. Remove catalytic converter (3).

8.3L ENGINE
1. Raise and support vehicle.
2. Saturate the bolts and nuts with heat valve lubri-
cant. Allow 5 minutes for penetration.
3. Disconnect oxygen sensor electrical connectors.
4. Remove LH exhaust pipe to manifold bolts (2),
retainers and nuts (1).
5. Remove LH catalytic converter to muffler clamp
nuts (4).
6. Rotate LH catalytic converters (6) from the muffler
(5).
7. Remove RH exhaust pipe to manifold bolts (2),
retainers and nuts (1).
8. Remove RH catalytic converter to muffler clamp
nuts (4).
9. Rotate RH catalytic converter (3) from the muffler
(5).
10. Remove clamps and nuts (4).
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 notbent or loose.
If you suspect internal damage to the catalyst, tapping the bottom of the catalyst with a rubber mallet may indicate
a damaged core.
INSTALLATION
3.7L/4.7L ENGINE
1. Install RH catalytic converter to exhaust clamp (4)
on RH catalytic converter (3) and position into
exhaust pipe (5).
2. Install and hand tighten RH catalytic converter to
exhaust manifold bolts (2).
3. Install c-clip nut (1) and bolt (2) to converter (3) to
manifold.
4. Tighten catalytic converter to exhaust manifold
bolts(1)to31Nꞏm(23ft.lbs.).
5. Tighten all clamp nuts (4) to 52.2 Nꞏm (40 ft. lbs.)
torque.
6. Check the exhaust system for contact with the
body panels. A minimum of 25 mm (1.0 in.) is
required between the exhaust system components
and body/frame parts. Make the necessary adjust-
ments, if needed.
7. Check to ensure you have at least 25 mm clear-
ance to oil pan.
8. Plug in O2 sensor wiring.
9. Lower the vehicle.
10. Start the engine and inspect for exhaust leaks. Repair exhaust leaks asnecessary.

MANUAL TRANSMISSION - G56 - SERVICE INFORMATION
DIAGNOSIS AND TESTING
MANUAL TRANSMISSION - G56
LOW LUBRICANT LEVEL
A low transmission lubricant level is generally the result of a leak, inadequate lubricant fill or incorrect lubricant level
check.
Rear transmission leakswill be from the oil seals or component mating surfaces.
Front transmission leakswill be from the front input shaft retainer seal. Lubricant may drip from theclutchhousing
after extended operation. If leak is severe, it may contaminate the clutchdisc.
Lubricant level checkcan only be made when the vehicle is level and allowing the lubricant to settle for a minute
before checking. This will ensure an accurate check and avoid an under or overfill condition.
HARD SHIFTING
Hard shifting is usually caused by low lubricant level, improper or contaminated lubricants. This will cause noise,
excessive wear, internal bind, and hard shifting. Substantial lubricantleaks can result in gear, shift rail, synchro, and
bearing damage. The first indications of component damage is usually hardshifting and noise.
Shift component damage, clutch adjustment, worn pressure plate or disc are also causes of increased shift effort. If
clutch problem is advanced, gear clash during shifts can result. Worn or damaged synchronizer rings can cause
gear clash when shifting into any forward gear. In some new or rebuilt transmissions, new synchro rings may tend
to stick slightly causing hard or noisy shifts. In most cases, this condition will decline as the rings wear-in.
TRANSMISSION NOISE
Most manual transmissions make some noise during normal operation. Rotating gears generate a mild whine that is
audible, but generally only at extreme speeds.
Severe, highly audible transmission noise is generally the initial indicator of a lubricant problem. Insufficient,
improper or contaminated lubricant will promote rapid wear of gears, synchronizer rings, shift rails, forks and bear-
ings. The overheating caused by a lubricant problem, can also lead to gear and bearing damage.

MANUAL TRANSMISSION - GETRAG 238 - SERVICE INFORMATION
DIAGNOSIS AND TESTING
MANUAL TRANSMISSION - GETRAG 238
LOW LUBRICANT LEVEL
A low transmission lubricant level is generally the result of a leak, inadequate lubricant fill or incorrect lubricant level
check.
Rear transmission leakswill be from the oil seals or transfer case front seal on 4x4.
Front transmission leakswill be from the front input shaft retainer seal. Lubricant may drip from theclutchhousing
after extended operation. If leak is severe, it may contaminate the clutchdisc.
Lubricant level checkcan only be made when the vehicle is level and allowing the lubricant to settle for a minute
before checking. This will ensure an accurate check and avoid an under or overfill condition.
HARD SHIFTING
Hard shifting can be caused by low lubricant level, improper or contaminated lubricants. This will cause noise,
excessive wear, internal bind, and hard shifting. Substantial lubricantleaks can result in gear, shift rail, synchro, and
bearing damage. The first indications of component damage is usually hardshifting and noise.
Shift component damage, clutch adjustment, worn pressure plate or disc, can increased shift effort. If clutch problem
is advanced, gear clash during shifts can result. Worn or damaged synchronizer rings can cause gear clash when
shifting into any forward gear. In some new or rebuilt transmissions, new synchro rings may tend to stick slightly
causing hard or noisy shifts. In most cases, this condition will decline asthe rings wear-in.
TRANSMISSION NOISE
Most manual transmissions make some noise during normal operation. Rotating gears generate a mild whine that is
audible, but generally only at extreme speeds.
Severe, highly audible transmission noise is generally the initial indicator of a lubricant problem. Insufficient,
improper or contaminated lubricant will promote rapid wear of gears, synchronizer rings, shift rails, forks and bear-
ings. The overheating caused by a lubricant problem, can also lead to gear and bearing damage.
STANDARD PROCEDURE
DRAIN AND FILL
1. Raise and support vehicle.
2. Remove drain plug (1) on transmission (2) and
drain fluid.
3. Install drain plug and tighten to 50 Nꞏm (37 ft. lbs.).

MANUAL TRANSMISSION-T56 - SERVICE INFORMATION
DIAGNOSIS AND TESTING
MANUAL TRANSMISSION - T56
LOW LUBRICANT LEVEL
A low transmission lubricant level is generally the result of a leak, inadequate lubricant fill or incorrect lubricant level
check.
Rear transmission leakswill be from the oil seals or component mating surfaces.
Front transmission leakswill be from the front bearing retainer or retainer seal. Lubricant may dripfromtheclutch
housing after extended operation. If leak is severe, it may contaminate the clutch disc.
Lubricant level checkcan only be made when the vehicle is level and allowing the lubricant to settle for a minute
before checking. This will ensure an accurate check and avoid an underfillor overfill condition.
HARD SHIFTING
Hard shifting is usually caused by low lubricant level, improper or contaminated lubricants. This will cause noise,
excessive wear, internal bind, and hard shifting. Substantial lubricantleaks can result in gear, shift rail, synchro, and
bearing damage. The first indications of component damage is usually hardshifting and noise.
Shift component damage, clutch adjustment, worn pressure plate or disc are also causes of increased shift effort. If
clutch problem is advanced, gear clash during shifts can result. Worn or damaged synchro rings can cause gear
clash when shifting into any forward gear. In some new or rebuilt transmissions, new synchro rings may tend to stick
slightly causing hard or noisy shifts. In most cases, this condition will decline as the rings wear-in.
TRANSMISSION NOISE
Most manual transmissions make some noise during normal operation. Rotating gears generate a mild whine that is
audible, but generally only at extreme speeds.
Severe, highly audible transmission noise is generally the initial indicator of a lubricant problem. Insufficient,
improper or contaminated lubricant will promote rapid wear of gears, synchros, shift rails, forks and bearings. The
overheating caused by a lubricant problem, can also lead to gear and bearing damage.
STANDARD PROCEDURE - DRAIN AND FILL
1. Raise and support vehicle.
2. Remove drain plug (1) on transmission tail housing
and drain fluid.
3. Install drain plug and tighten to 38 Nꞏm (28 ft. lbs.).
4. Remove transmission fill plug on left side of the
transmission case.
5. Fill transmission to bottom of the fill hole.
6. Install transmission fill plug and tighten to 27 Nꞏm
(20 ft. lbs.).

P0218-HIGH TEMPERATURE OPERATION ACTIVATED
For a complete wiring diagramRefer to Section 8W.
When Monitored:
Whenever the engine is running.
Set Condition:
Immediately when a Overheat shift schedule is activated when the Transmission Oil Temperature reaches 155°
C or 240° F.
Possible Causes
ENGINE COOLING SYSTEM OPERATION
TRANSMISSION OIL COOLER PLUGGED
H I G H T E M P E R AT U R E O P E R AT I O N S A C T I VAT E D
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 21 - TRANSMIS-
SION/TRANSAXLE/AUTOMATIC - 42RLE - STANDARD PROCEDURE)
Theory of Operation
If the transmission oil temperature rises above 115° C (240° F), the overheat shift schedule is activated refer to
Transmission Operation as a function of Transmission Oil Temperature andthe code is set. The DTC is an infor-
mational code only and is being set to aid the technician in determining root cause of a customer driveability issue.
The code is also intended to alert the technician to determine if a cooling system malfunction has occurred or if an
additional transmission air to oil cooler should be added to the vehicle ifthe customer regularly drives in a manner
that overheats the transmission. Extended operation above 115° C (240° F)will reduce the durability of the trans-
mission and should be avoided. Correcting the cooling system malfunctionor installing an additional transmission oil
cooler will improve transmission durability especially for customers who operate in city/construction stop and go traf-
fic, tow trailers regularly, drive aggressively in low gear or drive regularly in mountainous areas.
Diagnostic Test
1.CHECK ENGINE COOLING SYSTEM
Perform Engine Cooling System diagnostics per the Service Information.
Is the Engine Cooling System functioning properly?
Ye s>>
Go To 2
No>>
Repair the cause of the engine overheating. Refer to the Service Information for the related diagnostic
or repair procedures.
Perform 42RLE TRANSMISSION VERIFICATION TEST - VER 1. (Refer to 21 - TRANSMISSION/
TRANSAXLE/AUTOMATIC - 42RLE - STANDARD PROCEDURE)
2.TRANSMISSION OIL COOLER RESTRICTED
Check the Transmission Oil Cooler Flow in accordance with the Service Information.
Is the transmission oil cooler restricted or plugged?
Ye s>>
Go To 3
No>>
Repair the cause of the plugged Transmission Oil Cooler as necessary and repair or replace the Trans-
mission Oil Cooler per the Service Information.
Perform 42RLE TRANSMISSION VERIFICATION TEST - VER 1. (Refer to 21 - TRANSMISSION/
TRANSAXLE/AUTOMATIC - 42RLE - STANDARD PROCEDURE)

3.HIGH TEMPERATURE OPERATION
This DTC is an informational DTC designed to aid the Technician in diagnosing shift quality complaints.
This DTC indicates that the transmission has been operating in the
Overheatshift schedule which may generate
a customer complaint.
The customer driving patterns may indicate the need for an additional transmission oil cooler.
With the scan tool, check the DTC EVENT DATA to help identify the conditionsin which the DTC was set.
Check for any Service Information Tune-ups or Service Bulletins for any possible causes that may apply.
If there are no possible causes remaining, view repair.
Repair
Repair the cause of transmission overheating per the Service Information.
Perform 42RLE TRANSMISSION VERIFICATION TEST - VER 1. (Refer to 21 - TRANSMISSION/
TRANSAXLE/AUTOMATIC - 42RLE - STANDARD PROCEDURE)

P1797-MANUAL SHIFT OVERHEAT
For a complete wiring diagramRefer to Section 8W.
When Monitored:
Continuously with engine running.
Set Condition:
If the Engine Temperature exceeds 123° C (255° F) or the Transmission Temperature exceeds 135° C (275° F)
while in AutoStick
mode. Note: Aggressive driving or driving in low for extended periods of time will set this
DTC.
Possible Causes
MANUAL SHIFT OVERHEAT
Always perform the 42RLE Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 21 -
TRANSMISSION/TRANSAXLE/AUTOMATIC - 42RLE - STANDARD PROCEDURE)
Theory of Operation
The major cause of heat build up in the transmission is torque converter slip.WiththetransmissionintheAuto-
Stick
mode, the torque converter can slip during aggressive driving or heavy loading conditions such as trailer
towing or driving up steep grades. In the non AutoStick
mode, internal controller logic prevents the transmission
from overheating by managing the shift and EMCC schedule. In the AutoStick
mode, when the transmission or
engine temperature approaches an overheat condition, the manual shift overheat DTC sets and the AutoStick
mode is temporarily suspended until the temperature returns to normal.
Diagnostic Test
1.MANUAL SHIFT OVERHEAT
This is an informational DTC only.
With the scan tool, check the DTC EVENT DATA to help identify the conditionsin which the DTC was set.
Check the engine and transmission cooling system for proper operation.
Check the Radiator Cooling Fan operation.
Check the Transmission Cooling operation.
Check the Transmission Fluid Level per the Service Information to verify that it is not overfilled.
NOTE: Aggressive driving or driving in low for extended periods of time will set this DTC.
If there are no possible causes remaining, view repair.
Repair
If the Transmission Fluid is low, repair any Transmission Fluid leak as necessary and adjust the Trans-
mission Fluid Level per the Service Information. Refer to Service Information for the related symptoms
and repair as necessary.
Perform 42RLE TRANSMISSION VERIFICATION TEST - VER 1. (Refer to 21 - TRANSMISSION/
TRANSAXLE/AUTOMATIC - 42RLE - STANDARD PROCEDURE)