page page
MANUAL TRANSMISSION-T56 - SERVICE
INFORMATION
DIAGNOSIS AND TESTING
MANUAL TRANSMISSION - T56 ............. 143
STANDARD PROCEDURE - DRAIN AND FILL . . 143
REMOVAL ................................... 144
DISASSEMBLY .............................. 146
CLEANING .................................. 168
INSPECTION ................................ 168
ASSEMBLY .................................. 169
INSTALLATION .............................. 189
ADJUSTMENTS
ADUSTMENTS ............................ 191
SPECIFICATIONS
MANUAL TRANSMISSION - T56 ............. 192SPECIAL TOOLS ............................ 194
SEAL-EXTENSION HOUSING
REMOVAL ................................... 198
INSTALLATION .............................. 198
SHAFT-INPUT
REMOVAL ................................... 199
INSTALLATION .............................. 200
SOLENOID-REVERSE LOCKOUT
DESCRIPTION ............................... 201
OPERATION ................................. 201
SOLENOID-REVERSE LOCK-OUT
DESCRIPTION ............................... 202
OPERATION ................................. 202
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.).
P0122-TPS/APP CIRCUIT LOW
For a complete wiring diagramRefer to Section 8W.
When Monitored:
Continuously with the ignition on and engine running.
Set Condition:
This DTC will set if the monitored TPS voltage drops below .078 volts for theperiod of 0.48 seconds.
Possible Causes
RELATED TPS ENGINE DTCS PRESENT
POWERTRAIN CONTROL MODULE
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 21 - TRANSMIS-
SION/TRANSAXLE/AUTOMATIC - 42RLE - STANDARD PROCEDURE)
Theory of Operation
The powertrain controller receives the throttle position signal from theThrottle Position Sensor (TPS). The controller
provides the TPS with a 5 volt pull up and a sensor ground. The signal is checked for being out of range as well
as for intermittent operation (excessive signal changes). The engine controller transmits the throttle value onto the
Bus. Most engine controllers will calculate the throttle value if the throttle signal is lost. If an error is detected by the
transmission controller and the throttle value is available on the Bus, the Bus value will be used, normal operation
will continue, and a TPS code will be set. If an error is detected and the throttle value is not available on the Bus,
normal operation will be discontinued, a TPS DTC will be set, and the MIL will be turned on after 5 minutes of
calculated operation.
Diagnostic Test
1.DETERMINING IF RELATED ENGINE TPS DTCS ARE PRESENT
With the scan tool, check Engine DTCs, including pending DTCs and one trip failures.
Are there any Engine TPS DTCs present?
Ye s>>
Refer to the Driveability category and perform the appropriate diagnostic procedure.
Perform 42RLE TRANSMISSION VERIFICATION TEST - VER 1. (Refer to 21 - TRANSMISSION/
TRANSAXLE/AUTOMATIC - 42RLE - STANDARD PROCEDURE)
No>>
Go To 2
2.CHECK IF THE DTC IS CURRENT
With the scan tool, record the DTC EVENT DATA to help identify the conditionsinwhichtheDTCwasset.
With the scan tool, erase Transmission DTCs.
NOTE: To erase EVENT DATA information, a BATTERY DISCONNECT must be performed. Performing a BAT-
TERY DISCONNECT will reset all learned Transmission values to controllerdefaults which may lead to
erratic shift schedules.
Drive the vehicle and try to duplicate the conditions in which the DTC was reported by the DTC EVENT DATA.
With the scan tool, read Transmission DTCs.
Does this DTC reset?
Ye s>>
Using the schematics as a guide, check the Powertrain Control Module (PCM)terminals for corrosion,
damage, or terminal push out. Pay particular attention to all power and ground circuits. Check for Ser-
vice Information Tune-ups or Service Bulletins for any possible causes that may apply. If no problems
are found, replace the PCM per the Service Information. With the scan tool,perform QUICK LEARN.
Perform 42RLE TRANSMISSION VERIFICATION TEST - VER 1. (Refer to 21 - TRANSMISSION/
TRANSAXLE/AUTOMATIC - 42RLE - STANDARD PROCEDURE)
No>>
Go To 3
3.INTERMITTENT WIRING AND CONNECTORS
The conditions necessary to set this DTC are not present at this time.
Using the schematics as a guide, inspect the wiring and connectors specifictothiscircuit.
Wiggle the wires while checking for shorted and open circuits.
Pay particular attention to the TPS signal and sensor ground circuits.
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.
Were there any problems found?
Ye s>>
Repair as necessary.
Perform 42RLE TRANSMISSION VERIFICATION TEST - VER 1. (Refer to 21 - TRANSMISSION/
TRANSAXLE/AUTOMATIC - 42RLE - STANDARD PROCEDURE)
No>>
Te s t C o m p l e t e .
P0123-TPS/APP CIRCUIT HIGH
For a complete wiring diagramRefer to Section 8W
When Monitored:
Continuously with the ignition on and engine running.
Set Condition:
This DTC will set if the monitored TPS voltage rises above 4.94 volts for theperiod of 0.48 seconds.
Possible Causes
RELATED TPS ENGINE DTCS PRESENT
POWERTRAIN CONTROL MODULE
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 21 - TRANSMIS-
SION/TRANSAXLE/AUTOMATIC - 42RLE - STANDARD PROCEDURE)
Theory of Operation
The powertrain controller receives the throttle position signal from theThrottle Position Sensor (TPS). The controller
provides the TPS with a 5 volt pull up and a sensor ground. The signal is checked for being out of range as well
as for intermittent operation (excessive signal changes). The engine controller transmits the throttle value onto the
Bus. Most engine controllers will calculate the throttle value if the throttle signal is lost. If an error is detected by the
transmission controller and the throttle value is available on the Bus, the Bus value will be used, normal operation
will continue, and a TPS code will be set. If an error is detected and the throttle value is not available on the Bus,
normal operation will be discontinued, a TPS DTC will be set, and the MIL will be turned on after 5 minutes of
calculated operation.
Diagnostic Test
1.DETERMINING IF RELATED ENGINE TPS DTCS ARE PRESENT
With the scan tool, check Engine DTCs, including pending DTCs and one trip failures.
Are there any Engine TPS DTCs present?
Ye s>>
Refer to the Driveability category and perform the appropriate diagnostic procedure.
Perform 42RLE TRANSMISSION VERIFICATION TEST - VER 1. (Refer to 21 - TRANSMISSION/
TRANSAXLE/AUTOMATIC - 42RLE - STANDARD PROCEDURE)
No>>
Go To 2
2.CHECK TO SEE IF DTC IS CURRENT
With the scan tool, record the DTC EVENT DATA to help identify the conditionsinwhichtheDTCwasset.
With the scan tool, erase Transmission DTCs.
NOTE: To erase DTC EVENT DATA information, a BATTERY DISCONNECT must be performed. Performing a
BATTERY DISCONNECT will reset all learned Transmission values to controller defaults which may lead to
erratic shift schedules.
Drive the vehicle and try to duplicate the conditions in which the DTC was reported by the DTC EVENT DATA.
With the scan tool, read Transmission DTCs.
Does this DTC reset?
Ye s>>
Using the schematics as a guide, check the Powertrain Control Module (PCM)terminals for corrosion,
damage, or terminal push out. Pay particular attention to all power and ground circuits. Check for Ser-
vice Information Tune-ups or Service Bulletins for any possible causes that may apply. If no problems
are found, replace the PCM per the Service Information. With the scan tool,perform QUICK LEARN.
Perform 42RLE TRANSMISSION VERIFICATION TEST - VER 1. (Refer to 21 - TRANSMISSION/
TRANSAXLE/AUTOMATIC - 42RLE - STANDARD PROCEDURE)
No>>
Go To 3
3.INTERMITTENT WIRING AND CONNECTORS
The conditions necessary to set this DTC are not present at this time.
Using the schematics as a guide, inspect the wiring and connectors specifictothiscircuit.
Wiggle the wires while checking for shorted and open circuits.
Pay particular attention to the TPS signal and sensor ground circuits.
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.
Were there any problems found?
Ye s>>
Repair as necessary.
Perform 42RLE TRANSMISSION VERIFICATION TEST - VER 1. (Refer to 21 - TRANSMISSION/
TRANSAXLE/AUTOMATIC - 42RLE - STANDARD PROCEDURE)
No>>
Te s t C o m p l e t e .
3.CHECK THE THROTTLE POSITION SENSOR OPERATION
Ignition on, engine not running.
With the scan tool, under Transmission Sensors, monitor the TPS voltage inthe following step.
Slowly open and close the throttle while checking for erratic voltage changes.
Did the TPS voltage change smooth and consistent?
Ye s>>
Using the schematics as a guide, check the Powertrain Control Module (PCM)terminals for corrosion,
damage, or terminal push out. Pay particular attention to all power and ground circuits. Check for Ser-
vice Information Tune-ups or Service Bulletins for any possible causes that may apply. If no problems
are found, replace the PCM per the Service Information. With the scan tool,perform QUICK LEARN.
Perform 42RLE TRANSMISSION VERIFICATION TEST - VER 1. (Refer to 21 - TRANSMISSION/
TRANSAXLE/AUTOMATIC - 42RLE - STANDARD PROCEDURE)
No>>
Replace the Throttle Position Sensor per the Service Information.
Perform 42RLE TRANSMISSION VERIFICATION TEST - VER 1. (Refer to 21 - TRANSMISSION/
TRANSAXLE/AUTOMATIC - 42RLE - STANDARD PROCEDURE)
4.INTERMITTENT WIRING AND CONNECTORS
The conditions necessary to set this DTC are not present at this time.
Using the schematics as a guide, inspect the wiring and connectors specifictothiscircuit.
Wiggle the wires while checking for shorted and open circuits.
Pay particular attention to the TPS signal and sensor ground circuits.
With the scan tool, check the DTC EVENT DATA to help identify the conditionsin which the DTC was set.
Were there any problems found?
Ye s>>
Repair as necessary.
Perform 42RLE TRANSMISSION VERIFICATION TEST - VER 1. (Refer to 21 - TRANSMISSION/
TRANSAXLE/AUTOMATIC - 42RLE - STANDARD PROCEDURE)
No>>
Te s t C o m p l e t e .
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)