INFINITI QX56 2008 Factory Service Manual

TM-4
Precaution for Supplemental Restraint System
(SRS) "AIR BAG" and "SEAT BELT PRE-TEN-
SIONER" ................................................................
173
Precaution Necessary for Steering Wheel Rota-
tion After Battery Disconnect .................................
173
Precaution for On Board Diagnosis (OBD) System
of A/T and Engine ..................................................
174
Precaution .............................................................174
Service Notice or Precaution .................................175
PREPARATION ..........................................176
PREPARATION .............................................. .176
Special Service Tool ............................................ ..176
Commercial Service Tool ......................................177
ON-VEHICLE MAINTENANCE ..................178
A/T FLUID ....................................................... .178
Checking the A/T Fluid (ATF) .............................. ..178
Changing the A/T Fluid (ATF) ................................180
A/T FLUID COOLER ........................................182
A/T Fluid Cooler Cleaning ................................... ..182
Inspection ..............................................................184
STALL TEST ....................................................185
Inspection and Judgment .................................... ..185
LINE PRESSURE TEST ..................................187
Inspection and Judgment .................................... ..187
ROAD TEST .....................................................189
Description ........................................................... ..189
Check Before Engine Is Started ............................189
Check At Idle ....................................................... ..189
Cruise Test - Part 1 ...............................................190
Cruise Test - Part 2 ...............................................192
Cruise Test - Part 3 ...............................................193
Vehicle Speed When Shifting Gears .....................193
Vehicle Speed When Performing and Releasing
Complete Lock-up .................................................
193
A/T POSITION .................................................194
Checking of A/T Position ..................................... ..194
Adjustment of A/T Position ....................................194
ON-VEHICLE REPAIR ...............................195
SHIFT CONTROL SYSTEM ........................... .195
A/T Shift Selector Removal and Installation ..........195
Checking of A/T Position ..................................... ..196
Adjustment of A/T Position ....................................196
AIR BREATHER HOSE ...................................197
Removal and Installation ..................................... ..197
OIL PAN ...........................................................199
Oil Pan ................................................................. .199
CONTROL VALVE WITH TCM ........................201
Control Valve with TCM and A/T Fluid Tempera-
ture Sensor 2 ....................................................... .
201
REAR OIL SEAL ..............................................213
Rear Oil Seal ........................................................ .213
REMOVAL AND INSTALLATION .............214
TRANSMISSION ASSEMBLY ........................ ..214
Removal and Installation (2WD) .......................... .214
Removal and Installation (4WD) ...........................216
DISASSEMBLY AND ASSEMBLY ...........220
OVERHAUL ......................................................220
Component .......................................................... .220
Oil Channel ...........................................................227
Location of Adjusting Shims, Needle Bearings,
Thrust Washers and Snap Rings ......................... .
229
DISASSEMBLY .............................................. ..232
Disassembly ......................................................... .232
REPAIR FOR COMPONENT PARTS ..............250
Oil Pump .............................................................. .250
Front Sun Gear, 3rd One-Way Clutch ...................252
Front Carrier, Input Clutch, Rear Internal Gear .....254
Mid Sun Gear, Rear Sun Gear, High and Low Re-
verse Clutch Hub ................................................. .
259
High and Low Reverse Clutch ..............................264
Direct Clutch .........................................................266
ASSEMBLY .................................................... ..269
Assembly (1) ........................................................ .269
Adjustment ............................................................282
Assembly (2) .........................................................284
SERVICE DATA AND SPECIFICATIONS
(SDS) ........ .................................................
291
SERVICE DATA AND SPECIFICATIONS
(SDS) .............................................................. ..
291
General Specification ........................................... .291
Vehicle Speed at Which Gear Shifting Occurs .....291
Vehicle Speed at Which Lock-up Occurs/Releas-
es ......................................................................... .
291
Stall Speed ............................................................292
Line Pressure ........................................................292
A/T Fluid Temperature Sensor ..............................292
Input Speed Sensor ..............................................292
Output Speed Sensor ...........................................292
Reverse Brake ......................................................292
Total End Play .......................................................292
Torque Converter ..................................................293
Revision: March 2010 2008 QX56

DIAGNOSIS AND REPAIR WORKFLOWTM-5
< BASIC INSPECTION >
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BASIC INSPECTION
DIAGNOSIS AND REPAIR WORKFLOW
Work FlowINFOID:0000000001603985
INTRODUCTION
The TCM receives a signal from the output speed sensor, accelera-
tor pedal position sensor (throttle position sensor) or transmission
range switch. Then provides shift c ontrol or lock-up control via A/T
solenoid valves.
The TCM also communicates with the ECM by means of a signal
sent from sensing elements used wit h the OBD-related parts of the
A/T system for malfunction-diagnostic purposes. The TCM is capa-
ble of diagnosing malfunctioning parts while the ECM can store mal-
functions in its memory.
Input and output signals must always be correct and stable in the
operation of the A/T system. T he A/T system must be in good oper-
ating condition and be free of valve seizure, solenoid valve malfunc-
tion, etc.
It is much more difficult to diagnose an error that occurs intermit-
tently rather than continuously. Most intermittent errors are caused
by poor electric connections or impr oper wiring. In this case, careful
checking of suspected circuits may help prevent the replacement of
good parts.
A visual check only may not find t he cause of the errors. A road test
with CONSULT-III (or GST) or a circuit tester connected should be
performed. Follow the “DETAILED FLOW”.
Before undertaking actual checks, take a few minutes to talk with a
customer who approaches with a driveability complaint. The cus-
tomer can supply good information about such errors, especially
intermittent ones. Find out what symptoms are present and under
what conditions they occur. A “Diagnostic work sheet” as shown on
the example (Refer to TM-6
) should be used.
Start your diagnosis by looking for “conventional” errors first. This will
help troubleshoot driveability errors on an electronically controlled
engine vehicle.
Also check related Service bulletins.
DETAILED FLOW
1.COLLECT THE INFORMATION FROM THE CUSTOMER
Get the detailed information from the customer about the symptom (the condition and the environment when
the incident/malfunction occurred) us ing diagnosis worksheet. Refer to TM-6, "
Diagnostic Work Sheet".
>> GO TO 2.
2.CHECK SYMPTOM 1
Check the following items based on the in formation obtained from the customer.
• Fail-safe. Refer to TM-114, "
Fail-Safe".
• A/T fluid inspection. Refer to TM-178, "
Checking the A/T Fluid (ATF)".
• Stall test. Refer to TM-185, "
Inspection and Judgment".
• Line pressure test. Refer to TM-187, "
Inspection and Judgment".
SAT631IB
SAT632I
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Revision: March 2010 2008 QX56

TM-6
< BASIC INSPECTION >
DIAGNOSIS AND REPAIR WORKFLOW
>> GO TO 3.
3.CHECK DTC
1. Check DTC.
2. Perform the following procedure if DTC is detected.
• Record DTC.
• Erase DTC. Refer to TM-30, "
OBD-II Diagnostic Trouble Code (DTC)".
Is any DTC detected?
YES >> GO TO 4.
NO >> GO TO 6.
4.PERFORM DIAGNOSTIC PROCEDURE
Perform “Diagnosis Procedure” for the displayed DTC.
>> GO TO 5.
5.PERFORM DTC CONFIRMATION PROCEDURE
Perform “DTC CONFIRMATION PROCEDURE”.
Is DTC detected?
YES >> GO TO 4.
NO >> GO TO 6.
6.CHECK SYMPTOM 2
Try to confirm the symptom described by the customer.
Is any malfunction present?
YES >> GO TO 7.
NO >> INSPECTION END
7.ROAD TEST
Perform “ROAD TEST”. Refer to TM-189, "
Description".
>> GO TO 8.
8.CHECK SYMPTOM 3
Try to confirm the symptom described by the customer.
Is any malfunction present?
YES >> GO TO 2.
NO >> INSPECTION END
Diagnostic Work SheetINFOID:0000000001603986
INFORMATION FROM CUSTOMER
KEY POINTS• WHAT ..... Vehicle and A/T model
• WHEN ..... Date, Frequencies
• WHERE ..... Road conditions
• HOW ..... Operating conditions, Symptoms
Customer name MR/MS Model and Year VIN
Trans. Model EngineMileage
Malfunction Date Manuf. DateIn Service Date
Frequency † Continuous † Intermittent ( times a day)
Revision: March 2010 2008 QX56

DIAGNOSIS AND REPAIR WORKFLOWTM-7
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DIAGNOSTIC WORK SHEET
Symptoms † Vehicle does not move. ( † Any position † Particular position)
† No up-shift ( † 1st → 2nd † 2nd → 3rd † 3rd → 4th † 4th → 5th)
† No down-shift ( † 5th → 4th † 4th → 3rd † 3rd → 2nd † 2nd → 1st)
† Lock-up malfunction
† Shift point too high or too low.
† Shift shock or slip ( † N → D † N → R † Lock-up † Any drive position)
† Noise or vibration
† No kick down
† No pattern select
† Others
()
Malfunction indicator lamp (MIL) † Continuously lit † Not lit
1 †
Read the item on cautions concerning fail-safe and understand the customer's com-
plaint. TM-114
2†
A/T fluid inspection, stall test and line pressure test
† A/T fluid inspection
TM-178† Leak (Repair leak location.)
† Sta te
† Amount
3 †
Stall test
TM-185
† Torque converter one-way clutch
† Front brake
† High and low reverse clutch
† Low coast brake
† Forward brake
† Reverse brake
† Forward one-way clutch †
1st one-way
clutch
† 3rd one-way
clutch
† Engine
† Line pressure low
† Except for input
clutch and direct
clutch, clutches and
brakes OK
† Line pressure test - Suspected part: TM-187
4†
Perform self-diagnosis. — Check detected items to repair or replace malfunctioning
part. TM-32
5†
Perform road test.
5-1 † Check before engine is started TM-189
5-2† Check at idle TM-189
5-3Cruise test †
Part 1 TM-190† Part 2 TM-192
† Part 3 TM-193
† Check malfunction phenomena to repair or replace malfunctioning part after completing all road test.
Refer to TM-151, "
Symptom Table".
5 † Drive vehicle to check that the malfunction phenomenon has been resolved.
6 † Erase the results of the self-diagnosis from the TCM and the ECM. TM-30
Revision: March 2010 2008 QX56

TM-8
< FUNCTION DIAGNOSIS >
A/T CONTROL SYSTEM
FUNCTION DIAGNOSIS
A/T CONTROL SYSTEM
Cross-Sectional View (2WD models)INFOID:0000000001603987
1. Front planetary gear2. Mid planetary gear 3. Rear planetary gear
4. Direct clutch 5. High and low reverse clutch 6. Reverse brake
7. Drum support 8. Forward brake 9. Low coast brake
10. Input shaft 11. Torque converter 12. Oil pump
13. Front brake 14. 3rd one-way clutch 15. Input clutch
16. 1st one-way clutch 17. Control valve with TCM 18. Forward one-way clutch
19. Rear extension 20. Output shaft
SCIA5267E
Revision: March 2010 2008 QX56

A/T CONTROL SYSTEMTM-9
< FUNCTION DIAGNOSIS >
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Cross-Sectional View (4WD models)INFOID:0000000001603988
Shift MechanismINFOID:0000000001603989
The automatic transmission uses compact triple planet ary gear systems to improve power-transmission effi-
ciency, simplify construction and reduce weight.
It also employs an optimum shift control and super wide gear ratios. They improve starting performance and
acceleration during medium and high-speed operation.
CONSTRUCTION
1. Front planetary gear 2. Mid planetary gear 3. Rear planetary gear
4. Direct clutch 5. High and low reverse clutch 6. Reverse brake
7. Drum support 8. Forward brake 9. Low coast brake
10. Input shaft 11. Torque converter 12. Oil pump
13. Front brake 14. 3rd one-way clutch 15. Input clutch
16. 1st one-way clutch 17. Control valve with TCM 18. Forward one-way clutch
19. Adapter case 20. Output shaft
SCIA5268E
Revision: March 2010 2008 QX56

TM-10
< FUNCTION DIAGNOSIS >
A/T CONTROL SYSTEM
FUNCTION OF CLUTCH AND BRAKE
CLUTCH AND BAND CHART
1. Front brake 2. Input clutch3. Direct clutch
4. High and low reverse clutch 5. Reverse brake6. Forward brake
7. Low coast brake 8. 1st one-way clutch9. Forward one-way clutch
10. 3rd one-way clutch 11. Front sun gear12. Input shaft
13. Mid internal gear 14. Front internal gear15. Rear carrier
16. Rear sun gear 17. Mid sun gear18. Front carrier
19. Mid carrier 20. Rear internal gear21. Output shaft
22. Parking gear 23. Parking pawl
PCIA0002J
Name of the PartAbbreviation Function
Front brake (1) FR/B Fastens the front sun gear (11).
Input clutch (2) I/CConnects the input shaft (12), the front internal gear (14) and the mid internal
gear (13).
Direct clutch (3) D/C Connects the rear carrier (15) and the rear sun gear (16).
High and low reverse clutch (4) HLR/C Connects the mid sun gear (17) and the rear sun gear (16).
Reverse brake (5) R/B Fastens the rear carrier (15).
Forward brake (6) Fwd/B Fastens the mid sun gear (17).
Low coast brake (7) LC/B Fastens the mid sun gear (17).
1st one-way clutch (8) 1st OWCAllows the rear sun gear (16) to turn freely forward relative to the mid sun gear
(17) but fastens it
for reverse rotation.
Forward one-way clutch (9) Fwd OWCAllows the mid sun gear (17) to turn freely in the forward direction but fastens it
for reverse rotation.
3rd one-way clutch (10) 3rd OWCAllows the front sun gear (11) to turn freely in the forward direction but fastens
it for reverse rotation.
Shift position I/C HLR/C D
/C R/B FR/B LC/B Fwd/B 1st
OWC Fwd
OWC 3rd
OWC Remarks
P PARK POSITION
R REVERSE PO-
SITION
Revision: March 2010 2008 QX56

A/T CONTROL SYSTEMTM-11
< FUNCTION DIAGNOSIS >
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• —Operates
• —Operates during “pro gressive” acceleration.
• —Operates and effects power transmission while coasting.
• —Line pressure is applied but does not affect power transmission.
• —Operates under conditions shown in HLR/C Operating Condition
• —Operates under conditions shown in LC/B Operating Condition. Delay control is applied during D (4,3,2,1) ⇒N shift.
POWER TRANSMISSION
“N” Position
NNEUTRAL POSI-
TION
D 1st
Automatic shift
1 ⇔ 2⇔ 3⇔ 4⇔ 5
2nd
3rd
4th
5th1st
4 2nd
Automatic shift
3rd 1
⇔ 2⇔ 3⇔ 4
4th
3 1st
Automatic shift1⇔ 2⇔ 3⇐4
2nd
3rd 4th
2 1st
Automatic shift1⇔ 2⇐3 ⇐4
2nd
3rd
4th
1 1st
Locks (held sta-tionary in 1st gear)
1 ⇐ 2⇐3 ⇐4
2nd
3rd4th
Shift position I/C HLR/C D/C R/B FR/B LC/B Fwd/B
1st
OWC Fwd
OWC 3rd
OWC Remarks
SCIA5642E
Revision: March 2010
2008 QX56

TM-12
< FUNCTION DIAGNOSIS >
A/T CONTROL SYSTEM
Since both the forward brake and the reverse brake are released, torque from the input shaft drive is not trans-
mitted to the output shaft.
“P” Position
• The same as for the “N” position, both the forward br ake and the reverse brake are released, so torque from
the input shaft drive is not transmitted to the output shaft.
• The parking pawl linked with the select lever meshes with the parking gear and fastens the output shaft mechanically.
“D”, “4”, “3”, “2” Positions 1GR
• The forward brake and the forward one-way clutch regulate reverse rotation of the mid sun gear.
• The 1st one-way clutch regulates reverse rotation of the rear sun gear.
• The 3rd one-way clutch regulates reverse rotation of the front sun gear.
• During deceleration, the mid sun gear turns forward, so the forward one-way clutch idles and the engine
brake is not activated.
1. Front brake 2. Input clutch3. Direct clutch
4. High and low reverse clutch 5. Reverse brake 6. Forward brake
7. Low coast brake 8. 1st one-way clutch 9. Forward one-way clutch
10. 3rd one-way clutch 11. Front sun gear12. Input shaft
13. Mid internal gear 14. Front internal gear15. Rear carrier
16. Rear sun gear 17. Mid sun gear18. Front carrier
19. Mid carrier 20. Rear internal gear21. Output shaft
22. Parking gear 23. Parking pawl
PCIA0003J
Revision: March 2010 2008 QX56

A/T CONTROL SYSTEMTM-13
< FUNCTION DIAGNOSIS >
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“1” Position 1GR
• The front brake fastens the front sun gear.
• The forward brake and the forward one-way clutch
regulate reverse rotation of the mid sun gear.
• High and low reverse clutch connects the rear sun gear and the mid sun gear.
• The low coast brake fastens the mid sun gear.
• During deceleration, the low coast brake regulates forward rotation of the mid sun gear and the engine brake
functions.
1. Front brake 2. Input clutch3. Direct clutch
4. High and low reverse clutch 5. Reverse brake 6. Forward brake
7. Low coast brake 8. 1st one-way clutch9. Forward one-way clutch
10. 3rd one-way clutch 11. Front sun gear12. Input shaft
13. Mid internal gear 14. Front internal gear15. Rear carrier
16. Rear sun gear 17. Mid sun gear18. Front carrier
19. Mid carrier 20. Rear internal gear21. Output shaft
22. Parking gear 23. Parking pawl
SCIA1512E
Revision: March 2010 2008 QX56