suspension INFINITI QX4 2001 Factory Owner's Manual

NBST0043
NVH Troubleshooting ChartNBST0043S01Use the chart below to help you find the cause of the symptom. If necessary, repair or replace these parts.
Reference pageST-8
ST-9
ST-21
ST-21
ST-21
ST-8
ST-7
ST-9
MA-13
Ð
ST-13
ST-8
ST-13
ST-13
ST-17
PD-3
PD-3
AX-3
AX-3
SU-3
SU-3
SU-3
BR-6
Possible cause and
SUSPECTED PARTS
Fluid level
Air in hydraulic system
Tie-rod ball joint swinging force
Tie-rod ball joint rotating torque
Tie-rod ball joint end play
Steering gear fluid leakage
Steering wheel play
Steering gear rack sliding force
Drive belt looseness
Improper steering wheel
Improper installation or looseness or tilt lock lever
Mounting rubber deterioration
Steering column deformation or damage
Improper installation or looseness of steering column
Steering linkage looseness
PROPELLER SHAFT
DIFFERENTIAL
DRIVE SHAFT
AXLE
SUSPENSION
TIRES
ROAD WHEEL
BRAKES
Symp-
tomSTEERINGNoise´´´´´´´´´ ´´´´´´´´
Shake´´´ ´ ´´´´´´
Vibration´´´´´ ´ ´´´´
Shimmy´´´ ´ ´´´´´
Judder´ ´ ´´´´´
´: Applicable
NOISE, VIBRATION AND HARSHNESS (NVH) TROUBLESHOOTING
NVH Troubleshooting Chart
ST-6

SST489B
Checking Steering Wheel PlayNBST00051. With wheels in a straight-ahead position, check steering wheel
play.
Steering wheel play:
35 mm (1.38 in) or less
2. If it is not within specification, check the following for loose or
worn components.
Steering gear assembly
Steering column
Front suspension and axle
SST490BA
Checking Neutral Position on Steering WheelNBST0006PRE-CHECKINGNBST0006S01IMake sure that wheel alignment is correct.
Wheel alignment:
Refer to SU-13, ªWheel Alignmentº.
IVerify that the steering gear is centered before removing the
steering wheel.
CHECKINGNBST0006S021. Check that the steering wheel is in the neutral position when
driving straight ahead.
2. If it is not in the neutral position, remove the steering wheel and
reinstall it correctly.
3. If the neutral position is between two teeth, loosen tie-rod lock
nuts. Turn the tie-rods by the same amount in opposite direc-
tions on both left and right sides.
SMA127
Front Wheel Turning AngleNBST00071. Rotate steering wheel all the way right and left; measure turn-
ing angle.
Turning angle of full turns:
Refer to SU-13, ªWheel Alignmentº.
SST651C
2. If it is not within specification, check rack stroke.
Rack stroke ªSº:
Refer to SDS (ST-33).
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LC
EC
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PD
AX
SU
BR
RS
BT
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IDX
ON-VEHICLE SERVICE
Checking Steering Wheel Play
ST-7

FRONT & REAR SUSPENSION
SECTION
SU
CONTENTS
FRONT SUSPENSION....................................................2
Precautions ..................................................................2
PRECAUTIONS.........................................................2
Preparation ..................................................................2
SPECIAL SERVICE TOOLS........................................2
COMMERCIAL SERVICE TOOLS................................2
Noise, Vibration and Harshness (NVH)
Troubleshooting ...........................................................3
NVH TROUBLESHOOTING CHART............................3
Components.................................................................4
On-vehicle Service.......................................................5
FRONT SUSPENSION PARTS...................................5
FRONT WHEEL ALIGNMENT.....................................6
Coil Spring and Strut Assembly...................................8
COMPONENTS.........................................................8
REMOVAL.................................................................9
DISASSEMBLY..........................................................9
INSPECTION.............................................................9
ASSEMBLY.............................................................10
Stabilizer Bar .............................................................10
REMOVAL AND INSTALLATION...............................10
INSPECTION........................................................... 11
Transverse Link and Lower Ball Joint ....................... 11
REMOVAL AND INSTALLATION............................... 11
INSPECTION...........................................................12
Service Data and Specifications (SDS).....................13
GENERAL SPECIFICATIONS (FRONT).....................13
WHEEL ALIGNMENT (UNLADEN*1)..........................13
LOWER BALL JOINT...............................................13
WHEELARCH HEIGHT (UNLADEN*).........................14
WHEEL RUNOUT AVERAGE*..................................14
REAR SUSPENSION.....................................................15
Precautions ................................................................15
PRECAUTIONS.......................................................15
Preparation ................................................................15
COMMERCIAL SERVICE TOOLS..............................15
Noise, Vibration and Harshness (NVH)
Troubleshooting .........................................................15
Components...............................................................16
On-vehicle Service.....................................................16
REAR SUSPENSION PARTS...................................16
Removal and Installation ...........................................17
Coil Spring and Shock Absorber ...............................18
COMPONENTS.......................................................18
REMOVAL AND INSTALLATION...............................19
INSPECTION...........................................................19
Upper Link, Lower Link and Panhard Rod ................19
INSPECTION...........................................................19
BUSHING REPLACEMENT.......................................19
INSTALLATION........................................................20
Stabilizer Bar .............................................................20
REMOVAL AND INSTALLATION...............................20
Service Data and Specifications (SDS).....................20
GENERAL SPECIFICATIONS (REAR).......................20
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SBR686C
Precautions
PRECAUTIONSNBSU0001IWhen installing rubber parts, final tightening must be car-
ried out under unladen condition* with tires on ground.
*Fuel, radiator coolant and engine oil full. Spare tire, jack,
hand tools and mats in designated positions.
IUse flare nut wrench when removing and installing brake
tubes.
IAfter installing removed suspension parts, check wheel
alignment and adjust if necessary.
IAlways torque brake lines when installing.
Preparation
SPECIAL SERVICE TOOLSNBSU0002The actual shapes of Kent-Moore tools may differ from those of special service tools illustrated here.
Tool number
(Kent-Moore No.)
Tool nameDescription
ST29020001
(J24319-01)
Ball joint remover
NT694
Removing tie-rod outer end and lower ball joint
a: 34 mm (1.34 in)
b: 6.5 mm (0.256 in)
c: 61.5 mm (2.421 in)
COMMERCIAL SERVICE TOOLSNBSU0003
Tool name Description
1 Flare nut crowfoot
2 Torque wrench
NT360
Removing and installing each brake piping
a: 10 mm (0.39 in)
Spring compressor
NT717
Removing and installing coil spring
FRONT SUSPENSION
Precautions
SU-2

Noise, Vibration and Harshness (NVH)
Troubleshooting
=NBSU0035NVH TROUBLESHOOTING CHARTNBSU0035S01Use the chart below to help you find the cause of the symptom. If necessary, repair or replace these parts.
Reference page
SU-4, 16
SU-8, 18
Ð
Ð
Ð
SU-8, 18
SU-6
SU-10, 20
SU-6
Ð
Ð
Ð
Ð
Ð
Ð
PD-3
PD-3
AX-3
AX-3
Refer to SUSPENSION
in this chart.
Refer to TIRES
in this chart.
Refer to ROAD WHEEL
in this chart.
BR-6
ST-6
Possible cause and
SUSPECTED
PA R T S
Improper installation, looseness
Shock absorber deformation,
damage or deflection
Bushing or mounting deterioration
Parts interference
Spring fatigue
Suspension looseness
Incorrect wheel alignment
Stabilizer bar fatigue
Out-of-round
Imbalance
Incorrect air pressure
Uneven tire wear
Deformation or damage
Non-uniformity
Incorrect tire size
PROPELLER SHAFT
DIFFERENTIAL
DRIVE SHAFT
AXLE
SUSPENSION
TIRES
ROAD WHEEL
BRAKES
STEERING Symptom
SUSPENSION
Noise´ ´ ´´´´ ´´´´ ´ ´ ´´
Shake´´´´´ ´´´ ´´´´
Vibration´ ´ ´´´ ´ ´´ ´ ´
Shimmy´´´´ ´ ´ ´ ´´´
Judder´´´ ´ ´ ´´´
Poor quality
ride or han-
dling´ ´ ´´´ ´´ ´ ´ ´
TIRES
Noise´ ´´´´´´ ´´´´ ´ ´ ´´
Shake´ ´´´´´ ´´ ´´ ´ ´ ´´
Vibration´´´´´´ ´
Shimmy´ ´´´´´´´ ´ ´ ´ ´´
Judder´ ´´´´´ ´ ´ ´ ´ ´´
Poor quality
ride or han-
dling´ ´´´´´ ´ ´ ´ ´
ROAD WHEEL
Noise´ ´´ ´ ´´´´ ´ ´ ´´
Shake´ ´´ ´ ´ ´´ ´ ´ ´´
Shimmy,
Judder´´´´´´´´´
Poor quality
ride or han-
dling´´´´´´´
´: Applicable
GI
MA
EM
LC
EC
FE
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PD
AX
BR
ST
RS
BT
HA
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IDX
FRONT SUSPENSION
Noise, Vibration and Harshness (NVH) Troubleshooting
SU-3

ComponentsNBSU0004
SFA744B
1. Strut mounting insulator
2. Spring upper seat
3. Bound bumper
4. Coil spring5. Strut assembly
6. Stabilizer connecting rod
7. Bracket8. Stabilizer bar
9. Transverse link
10. Drive shaft
FRONT SUSPENSION
Components
SU-4

SMA525A
On-vehicle Service
FRONT SUSPENSION PARTSNBSU0005Check front axle and front suspension parts for excessive play,
cracks, wear and other damage.
1. Shake each front wheel to check for excessive play.
2. Retighten all axle and suspensions nuts and bolts to the speci-
fied torque.
Tightening torque:
Refer to ªComponentsº, SU-8.
SFA392B
3. Check strut (shock absorber) for oil leakage and other dam-
age.
4. Check suspension ball joint for grease leakage and ball joint
dust cover for cracks and other damage.
If ball joint dust cover is cracked or damaged, replace ball joint
assembly.
5. Check suspension ball joint end play.
a. Jack up front of vehicle and set the stands.
b. Clamp dial indicator onto transverse link and place indicator tip
on lower edge of brake caliper.
c. Make sure front wheels are straight and brake pedal is
depressed.
SFA745B
d. Place a pry bar between transverse link and knuckle.
e. While raising and releasing pry bar, observe maximum dial
indicator value.
Vertical end play:
0mm(0in)
If ball joint vertical end play exists, remove lower ball joint
assembly and recheck the ball joint. Refer to ªTranverse Link
and Lower Ball Jointº, SU-11.
SFA746B
6. Check spring height from top of wheelarch to ground using the
following procedure.
a. Park vehicle on a level surface with vehicle unladen*.
*: Fuel, radiator coolant and engine oil full. Spare tire, jack,
hand tools and mats in designated positions.
b. Check tires for proper inflation and wear (tread wear indicator
must not be showing).
c. Bounce vehicle up and down several times and measure
dimensions Hf and Hr. Refer to SDS, SU-14.
Spring height is not adjustable. If out of specification, check for
worn springs and suspension parts.
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FRONT SUSPENSION
On-vehicle Service
SU-5

SFA975B
FRONT WHEEL ALIGNMENTNBSU0006Before checking front wheel alignment, be sure to make a prelimi-
nary inspection (Unladen*).
*: Fuel, radiator coolant and engine oil full. Spare tire, jack, hand
tools and mats in designated positions.
Preliminary InspectionNBSU0006S011. Check tires for wear and improper inflation.
2. Check wheels for deformation, cracks and other damage.
If deformed, remove wheel and check wheel runout.
NOTE:
Measure both the inner and outer sides for the radial runout and
lateral runout, and confirm the figures are within the standards.
Wheel runout (Dial indicator value):
Refer to SDS.
3. Check front wheel bearings for looseness.
4. Check front suspension for looseness.
5. Check steering linkage for looseness.
6. Check that front shock absorbers work properly.
7. Check vehicle posture (Unladen).
SFA894
Camber, Caster and Kingpin InclinationNBSU0006S02Camber, caster and kingpin inclination are preset at factory
and cannot be adjusted.
1. Measure camber, caster and kingpin inclination of both right
and left wheels with a suitable alignment gauge.
Camber, Caster and Kingpin inclination:
Refer to SDS, SU-13.
2. If camber, caster or kingpin inclination is not within
specification, inspect front suspension parts. Replace dam-
aged or worn out parts.
FRONT SUSPENSION
On-vehicle Service (Cont'd)
SU-6

SFA614B
SFA234AC
Toe-inNBSU0006S03Measure toe-in using the following procedure.
WARNING:
IAlways perform the following procedure on a flat surface.
IMake sure that no person is in front of the vehicle before
pushing it.
1. Bounce front of vehicle up and down to stabilize the posture.
2. Push the vehicle straight ahead about 5 m (16 ft).
3. Put a mark on base line of the tread (rear side) of both tires at
the same height of hub center. This mark is a measuring point.
4. Measure distance ªAº (rear side).
5. Push the vehicle slowly ahead to rotate the wheels 180
degrees (1/2 turn).
If the wheels have rotated more than 180 degrees (1/2 turn), try
the above procedure again from the beginning. Never push
vehicle backward.
6. Measure distance ªBº (front side).
Total toe-in:
Refer to SDS, SU-13.
SFA749B
7. Adjust toe-in by varying the length of steering tie-rods.
a. Loosen lock nuts.
b. Adjust toe-in by screwing tie-rods in and out.
SFA486A
Make sure both tie-rods are the same length.
Standard length ªLº:
Refer to ST-33, ªSteering Gear and Linkageº.
c. Tighten lock nuts to specified torque.
Lock nut tightening torque:
Refer to ST-17, ªPOWER STEERING GEAR AND LINK-
AGEº.
SFA439BA
Front Wheel Turning AngleNBSU0006S04Turning angle is set by stroke length of steering gear rack and
cannot be adjusted.
1. Set wheels in straight-ahead position. Then move vehicle for-
ward until front wheels rest on turning radius gauge properly.
2. Rotate steering wheel all the way right and left; measure turn-
ing angle.
Do not hold the steering wheel on full lock for more than 15
seconds.
Wheel turning angle (Full turn):
Refer to SDS, SU-13.
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IDX
FRONT SUSPENSION
On-vehicle Service (Cont'd)
SU-7

Coil Spring and Strut Assembly
COMPONENTSNBSU0007
SFA764BA
1. Spacer
2. Strut mounting insulator
3. Bracket
4. Strut mounting bearing
5. Spring upper seat
6. Bound bumper
7. Coil spring
8. (Polyurethane tube)9. Strut assembly
10. Bracket
11. Lower ball joint assembly
12. Cotter pin
13. Transverse link
14. Stabilizer connecting rod
15. Stabilizer bar16. Bushing
17. Bracket
18. Knuckle spindle
19. Snap ring
20. Hub cap
21. Drive shaft
22. Cap
FRONT SUSPENSION
Coil Spring and Strut Assembly
SU-8