2005 LEXUS ES300 wheel alignment

Lexus Supports ASE CertificationPage 1 of 11
Title:
REPAIR MANUAL SUPPLEMENT:
VEHICLE PULLING TO ONE SIDE
Models:
All '02 ± '06 Model
Technical Service
Information Bulletin
December 21, 2001
ST004-01
TSIB REVISION NOTICE:
October 5, 2005: 2003 ± 2006 model years have been added to Applicable Vehicles.
A note has been added to the illustration in step 3.
March 1, 2002: OP Codes updated in Warranty Information.
All previous versions of this TSIB should be discarded.
This bulletin contains general vehicle pulling diagnosis and repair procedures along with
specific information to help correct pulling complaints.
This information supplements Repair Manual procedures when the symptoms are:
The driver holds the steering wheel without exerting steering effort while driving
straight ahead, and the vehicle drifts to the right or the left.
While driving straight ahead, the driver has to steer either to the right or the left to
maintain straight driving.
2002 ± 2006 model year Lexus vehicles.
OP CODEDESCRIPTIONTIMEOPNT1T2
ST1004Preliminary Check & Road Test0.6
Combo ASwitch Front Tire/Wheel & Road Test0.5
Combo BReverse the Front One Side Tire0.745046 09020Combo CCheck Front Wheel Alignment1.245046±09020
Combo DAdjust Front Wheel Alignment0.73199
Combo EAdjust Camber Setting0.7
420091Dismount and Mount Tire and Balance Wheel
and Tire Assembly0.542611±48030
Combo AEach additional Wheel0.3
42611 48030
NOTE:
Above combination codes A, B, D and E include road test time.
Applicable Warranty*:
This repair is covered under the Lexus Comprehensive Warranty. This warranty is in
effect for 12 months or 20,000 miles, whichever occurs first, from the vehicle's
in-service date.
* Warranty application is limited to correction of a problem based upon a customer's specific complaint.
STEERING
Introduction
Applicable
Vehicles
Warranty
Information

REPAIR MANUAL SUPPLEMENT: VEHICLE PULLING TO ONE SIDE ± ST004-01 RevisedDecember 21, 2001
Page 2 of 11
This bulletin is divided into the following sections:
Wheel Alignment and Tire Characteristics Pages 2±3. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Repair Procedure Flow Chart Page 4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Repair Procedures
1. Important Notice Page 5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2. Troubleshooting Pages 5±6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3. Vehicle Pulling Caused by Wheel Alignment Pages 6±7. . . . . . . . . . . . . . . . . . .
4. Vehicle Pulling Caused by Tire Conicity Pages 7±9. . . . . . . . . . . . . . . . . . . . . . .
5. Camber Adjustment Method Pages 9±10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Contents

REPAIR MANUAL SUPPLEMENT: VEHICLE PULLING TO ONE SIDE ± ST004-01 RevisedDecember 21, 2001
Page 3 of 11
1. Relationship Between Wheel Alignment and Vehicle Pulling to One Side
When the cross camber or caster of the front wheel alignment is large, it can cause
vehicle pulling.
WHEEL ALIGNMENTDIRECTION OF VEHICLE PULLING
CamberVehicle pulls in direction of wheel with large camber value
CasterVehicle pulls in direction of wheel with small caster value
CAMBER
Straight±Ahead
DrivingDirection of Pull
CASTER
Front
Caster Trail
(Small)Caster Trail
(Large) TPT' P'
F' F aa'
O
P, P': Driving Force
a, a': Steering Axes
O, O': Center of Tire±Road
Contact Area
F, F': Reactive Force
O'
If the cross camber or caster is within the specified range (30' or less), noticeable vehicle
pulling will not occur due to side-to-side differences in camber or caster.
NOTE:
On a flat road, if the cross camber or caster is 30' or less and the steering wheel is
held without exerting steering effort for 100 m (109 yards) when driving at 100 km/h
(62 mph), the alignment±induced drift distance is approximately 0.5 m (1.64 ft). Wheel
Alignment &
Tire
Characteristics

REPAIR MANUAL SUPPLEMENT: VEHICLE PULLING TO ONE SIDE ± ST004-01 RevisedDecember 21, 2001
Page 4 of 11
2. Relationship Between Tire Characteristics and Vehicle Pulling to One Side
When radial tires are rotating, they have the characteristic of generating force in the
lateral direction between the tire and the road surface. This lateral force is comprised
of two factors:
Ply±steer, which changes direction according to the rotation direction of the tires.
Conicity, which is generated in a fixed direction regardless of the tire rotation
direction.
If these lateral forces are too strong, vehicle pulling will occur.
A. Ply±Steer
Lateral force due to ply-steer is produced by the construction of the belts inside
the tire tread. With radial tires, the wire of the belt is slanted as shown in the
illustration below. Thus, it is in the lateral direction that tire tread easily changes
shape (stretches), and lateral force is generated between the tire and the road
surface in the lateral direction.
Easily±Stretched
Direction
Wire
BeltRotation Direction
Ply±Steer
(Direction of Force Generation Varies
According to Tire Rotation)
NOTE:
Lateral force from ply-steer prevents vehicle drift caused by road slant, so in many
cases lateral force to the right is provided for left-handed steering vehicles.
B. Conicity
Conicity is lateral force resulting from uneven formation of the left and right sides
of the tire. The direction the lateral force is exerted depends on the hardness of
the side walls and the difference in height between the left/right sides of the tire.
Conicity
(Direction Is Fixed Regardless of
Direction of Tire Rotation) Hard
Part
NOTE:
In the case of vehicle pulling caused by tires, the lateral force which is exerted as a
result of conicity has the greatest effect. On a flat road, if the steering wheel is held
without exerting steering effort for 100 m (109 yards) when travelling at 100 km/h (62
mph), the vehicle may drift as much as 1.5 m (5 ft).
When vehicle pulling is due to conicity, the amount of drift can be reduced and the
direction of drift can be changed by changing the location of the tire or reversing
the tire when installing it on the wheel. Wheel
Alignment &
Tire
Characteristics
(Continued)

REPAIR MANUAL SUPPLEMENT: VEHICLE PULLING TO ONE SIDE ± ST004-01 RevisedDecember 21, 2001
Page 5 of 11
* Select a flat road where the vehicle can be driven in a straight line for 100 meters at a constant speed of
35 mph. Please confirm safety and set the steering wheel to its straight position. Drive the vehicle in a
straight line for 100 meters at a constant speed of 35 mph without exerting steering effort on the steering
wheel.
(1) The vehicle goes straight but the steering wheel has some angle. STEERING OFF CENTER
(2) The vehicle doesn't go straight. STEERING PULLYES
START
Preliminary Check
Tire Pressure
Vehicle height
Brake Dragging*ROAD TEST
Does the vehicle lead/pull?Is there steering
off center?COMPLETE
Adjust front tie rods.
See TSIB ST002±01
Are the tires uni±directional type?
Cross switch front tire and wheel
assemblies (left & right)ROAD TEST
Does the vehicle still lead/pull?
Does the vehicle lead/pull in the
same direction as before?
Is the lead/pull stronger
than before?
Reverse the front left side
tire and rebalance it.
ROAD TEST
Does the vehicle still lead/pull?
Increase left front camber and decrease right
front camber until lead/pull is eliminated.
Does the vehicle
lead/pull to the left?
ROAD TEST
Does the vehicle still lead/pull?
Increase right front camber and decrease left
front camber until lead/pull is eliminated.
Contact your regional office.
COMPLETE
Choose the position of front tire & wheel
assemblies where there is least amount of pull.
Check front wheel alignment.
Is it within specification?
ROAD TEST
Does the vehicle still lead/pull?
Adjust front wheel alignment.
NOTE: Do not exceed 1
of
cross camber.
Do not exceed adjustment range.
NO YES YES
YES
YES
YESNO
NO YES
NO NO YESNO YESYES YES
NONO NO
NO NO
Repair
Procedure
Flow Chart

REPAIR MANUAL SUPPLEMENT: VEHICLE PULLING TO ONE SIDE ± ST004-01 RevisedDecember 21, 2001
Page 6 of 11
1. IMPORTANT NOTICE
Before repairing vehicle pulling to one side, it is necessary to clearly identify the
cause of the pulling condition. Frequently, the cause of the vehicle pulling to one side
is diagnosed as wheel alignment. However, the actual cause may be lateral force
generated by the tires. Performing wheel alignment when tire force is the cause could
result in the wheel alignment being set at a value outside of specifications. This would
then cause other problems such as uneven tire wear, etc.
2. Troubleshooting
First determine whether vehicle pulling to one side is caused by a wheel alignment
problem or tire characteristics, then decide which repairs to make.
A. Perform the following checks and correct as necessary.
a. Check tires for size, wear and for proper inflation pressure.
b. Check whether the vehicle is noticeably tilted backward/forward or left/right.
NOTE:
Tilting of the vehicle produces a left±right difference in the camber and caster and can
cause vehicle pulling to one side.
c. Check brakes for dragging.
B. Confirm problem symptoms.
With the customer accompanying you, drive the vehicle to confirm if the
customer 's complaint involves vehicle pulling to one side or steering wheel off
center. If the problem is steering wheel off center, adjust the front tie rods on the
vehicle. Refer to Lexus TSIB ST002±01. Also check the direction of vehicle
pulling and the extent of the pulling.
C. Decide if vehicle pulling is due to wheel alignment or tires.
a. Switch the left and right front tires (If the tires are non±unidirectional).
b. Conduct a drive test to check whether the direction that the vehicle pulls has
changed.
SYMPTOMPROBABLE CAUSECORRECTIVE ACTION
No change in vehicle
pulling conditionFront wheel alignmentProceed to Repair Procedure 3. Vehicle pulling
caused by Wheel Alignment (Page 6)
Vehicle pulling
eliminatedTire conicityRepair complete. Vehicle Pulling Caused by Tire
Conicity (Page 3 and 6)
Vehicle pulling
direction is reversedTire conicityProceed to Repair Procedure 4. Vehicle Pulling
Caused by Tire Conicity (Page 7)
Repair
Procedures

REPAIR MANUAL SUPPLEMENT: VEHICLE PULLING TO ONE SIDE ± ST004-01 RevisedDecember 21, 2001
Page 7 of 11
Helpful hints to determine cause of vehicle pulling:
The direction of lateral force from tire conicity becomes reversed when the left and
right tires are switched. Therefore, if the pulling direction changes when the tires are
switched, it can be concluded that vehicle pulling is caused by tire conicity.
ORIGINAL TIRE POSITIONS TIRES SWITCHED
The Vehicle is Pulled to the Right by
the Lateral Force Exerted to the Right.The Direction of the Tires Which Exerted Lateral
Force to the Right has Been Changed, so the Tires
Now Exert Lateral Force to the Left and the Vehicle
Now Pulls to the Left. Vehicle Pulling
Direction (Right)Vehicle Pulling
Direction (Left)
Lateral Force by
ConicityLateral Force by
Conicity
If the pulling direction does not change after the front tires are switched, the cause of
vehicle pulling is not tire conicity. In this case, the likely cause is a front wheel
alignment condition.
3. Vehicle Pulling Caused by Wheel Alignment
When it is determined by troubleshooting that the vehicle pulling to one side is
caused by wheel alignment, perform repairs according to the following procedure.
Vehicle Pulling to One Side
Check Front Wheel Alignment
Not Within SpecificationWithin Specification
Adjust Front Wheel Alignment
Vehicle Still Pulls
Road Test
Within Specification But
Vehicle Pulls
OK
Adjust Cross Camber to Eliminate Vehicle Pulling
NOTE: Do not exceed 1
of cross camber.
Repair
Procedures
(Continued)

REPAIR MANUAL SUPPLEMENT: VEHICLE PULLING TO ONE SIDE ± ST004-01 RevisedDecember 21, 2001
Page 10 of 11
STEP 3:
Adjust cross camber to eliminate vehicle pulling.
HINT:
If the tires are placed in the positions they were in during tire rotation when the least
amount of vehicle pulling occurred, wheel alignment can be performed with a minimal
amount of adjustment.
WHEN VEHICLE PULLS TO LEFTWHEN VEHICLE PULLS TO RIGHT
Increase right front camber and decrease left
front camber until vehicle pulling is eliminatedIncrease left front camber and decrease right
front camber until vehicle pulling is eliminated
NOTE:
Keep the cross camber within 1
or less.
Keep the camber of each wheel within specifications (+/±45' of center value).
If adjustment exceeds the specifications, uneven tire wear will result.
5. Camber Adjustment Method
NOTE:
After the camber has been adjusted,
inspect the toe±in.
NOTE:
The method of camber adjustment
differs for different models, so please
refer to the repair manual of the
vehicle involved. (This is a sample
from the RX 300 Repair Manual).
A. Remove the front wheels and
ABS speed sensor clamp.
B. Remove the two nuts on the lower
side of the shock absorber.
C. Coat the threads of the nuts with
engine oil.
D. Temporarily install the two nuts.
E. Adjust the camber by pushing or
pulling the lower side of the shock
absorber in the direction in which
the camber adjustment is
required.
F. Tighten the nuts.
Torque: 210 Nm
(2,150 kgfcm, 155 ftlbf)
Repair
Procedures
(Continued)
1
2