2A – 6ISUSPENSION DIAGNOSIS
DAEWOO V–121 BL4
S A high front trim height. This height would increase
the drive axle angle and could cause wobble at
speeds between 24 to 48 km/h (15 to 30 mph).
S Binding or a tight drive axle joint. A tight drive axle
joint or a high front trim height may also cause a
wobble at speeds between 24 to 48 km/h (15 to 30
mph).
S Incorrect, worn, or loose engine mounts causing
adverse drive angles.
Refer to ”General Diagnosis” in this section for actions to
remedy these problems.
Conditions that may produce an effect similar to torque
steer include:
S Incorrect front or rear alignment.
S Frame misalignment or defect.
S Front suspension damage.
S Incorrectly mounted rear crossmember.
TAPERED ROLLER BEARING
Perform the following test to check for looseness in the
hub and bearing assembly on vehicles equipped with rear
disc brakes:
1. Raise and suitably support the vehicle.
2. Remove the rear wheel. Refer to Section 2E, Tires
and Wheels.
3. Remove the brake disc caliper and the brake rotor.
Refer to Section 4E1, Rear Disc Brakes.4. Mount a dial indicator set with a magnetic base to a
control arm or any other stationary part of the ve-
hicle.
5. Push and pull the wheel hub by hand. If the wheel
hub movement exceeds 0.05 mm (0.002 inch), re-
place the wheel bearing. Refer to Section 2D, Rear
Suspension.
6. Install the brake disc caliper and the brake rotor.
Refer to Section 4E1, Rear Disc Brakes.
7. Install the rear wheel. Refer to Section 2E, Tires
and Wheels.
8. Lower the vehicle.
SECTION : 2B
WHEEL ALIGNMENT
TABLE OF CONTENTS
SPECIFICATIONS2B–1 . . . . . . . . . . . . . . . . . . . . . . . . . .
Wheel Alignment Specifications 2B–1. . . . . . . . . . . . . .
Fastener Tightening Specifications 2B–1. . . . . . . . . . .
DIAGNOSIS2B–2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Tire Diagnosis 2B–2. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Radial Tire Lead/Pull 2B–3. . . . . . . . . . . . . . . . . . . . . . .
Vibration Diagnosis 2B–5. . . . . . . . . . . . . . . . . . . . . . . .
Preliminary Inspection 2B–8. . . . . . . . . . . . . . . . . . . . . .
Front Toe Adjustment 2B–8. . . . . . . . . . . . . . . . . . . . . .
Front Camber and Caster Check 2B–8. . . . . . . . . . . . .
Rear Camber Check 2B–8. . . . . . . . . . . . . . . . . . . . . . . Rear Toe Adjustment 2B–9. . . . . . . . . . . . . . . . . . . . . . .
GENERAL DESCRIPTION AND SYSTEM
OPERATION2B–10 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Four Wheel Alignment 2B–10. . . . . . . . . . . . . . . . . . . . .
Toe 2B–10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Caster 2B–10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Camber 2B–10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Steering Axis Inclination 2B–10. . . . . . . . . . . . . . . . . . .
Included Angle 2B–10. . . . . . . . . . . . . . . . . . . . . . . . . . .
Scrub Radius 2B–10. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Setback 2B–10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Turning Angle 2B–10. . . . . . . . . . . . . . . . . . . . . . . . . . . .
SPECIFICATIONS
WHEEL ALIGNMENT SPECIFICATIONS
ApplicationFrontRear
Camber–0°20’ ± 45’–1°00’ ± 45’
Caster4°00’ ± 45’–
Toe–in (No person, full tank)0°00 ± 10’0°12’ ± 10’
FASTENER TIGHTENING SPECIFICATIONS
ApplicationNSmLb–FtLb–In
Rear Parallel Link–to–Crossmember Nut9066–
2B – 2IWHEEL ALIGNMENT
DAEWOO V–121 BL4
DIAGNOSIS
TIRE DIAGNOSIS
Irregular and Premature Wear
Irregular and premature tire wear has many causes. Some
of them are incorrect inflation pressures, lack of regular
rotation, poor driving habits, or improper wheel alignment.
If the wheel alignment is reset because of tire wear, always
reset the toe as close to zero degrees as the specification
allows. Refer to ”Rear Toe Adjustment” in this section.
Rotate the tires if:
S The front tire wear is different from the rear.
S The left and right front tire wear is unequal.
S The left and right rear tire wear is unequal.
Check wheel alignment if:
S The left and right front tire wear is unequal.
S The wear is uneven across the tread of either front
tire.
S The front tire treads are scuffed with ”feather”
edges on the side of the tread ribs or blocks.
Tread Wear Indicators
The original equipment tires have built–in tread wear indi-
cators to show when the tires need replacement. These in-
dicators appear as bands when the tire tread depth be-
comes shallow. Tire replacement is recommended when
the indicators appear in three or more grooves at six loca-
tions.
Radial Tire Waddle
Waddle is side–to–side movement at the front or rear of
the vehicle. It is caused by the steel belt not being straight
within the tire, or by excessive lateral runout of the tire or
wheel. It is most noticeable at low speeds, 8 to 48 km/h (5
to 30 mph), but may appear as ride roughness at 80 to 113
km/h (50 to 70 mph).
The vehicle must be road tested to determine which end
of the vehicle has the faulty tire. The rear end of the vehicle
will shake from side to side or ”waddle” if the waddle tire
is on the rear of the vehicle. From the driver’s seat, it feels
as though someone is pushing on the side of the vehicle.
If the faulty tire is on the front of the vehicle, the waddle is
more visual. The front sheet metal appears to be moving
back and forth, and the driver’s seat feels like the pivot
point in the vehicle.
Waddle can be diagnosed using the method of substi–tut-
ing known good tire and wheel assemblies on the problem
vehicle.
1. Road test the vehicle to determine if the waddle is
coming from the front or the rear of the vehicle.
2. Install good tires and wheels from a similar vehicle
in place of those on the offending end of the prob-
lem vehicle. If the source of the waddle is not ob-
vious, change the rear tires.
3. Road test the vehicle. If there is improvement,
install the original tires to find the offending tire. If
there is no improvement, install good tires in place
of all four offending tires.
WHEEL ALIGNMENT 2B – 5
DAEWOO V–121 BL4
VIBRATION DIAGNOSIS
Wheel imbalance causes most highway speed vibration
problems. A vibration can remain after dynamic balancing
because:
S A tire is out of round.
S A rim is out of round.
S A tire stiffness variation exists.
Measuring tire and wheel free runout will uncover only part
of the problem. All three causes, known as loaded radial
runout, must be checked using method of substituting
known good tire and wheel assemblies on the problem ve-
hicle.
Low–speed vibrations, which occur below 64 km/h (40
mph), are usually caused by runout. High–speed vibra-
tions, which occur above 64 km/h (40 mph), can be caused
by either imbalance or runout.
Preliminary Checks
Prior to performing any work, always road test the car and
perform a careful visual inspection for:
S Obvious tire and wheel runout.
S Obvious drive axle runout.
S Improper tire inflation.
S Incorrect trim height.
S Bent or damaged wheels.
S Debris build–up on the tire or the wheel.
S Irregular or excessive tire wear.
S Improper tire bead seating on the rim.
S Imperfections in the tires, including: tread deforma-
tions, separations, or bulges from impact damage.
Slight sidewall indentations are normal and will not
affect ride quality.
Tire Balancing
Balance is the easiest procedure to perform and should be
done first if the vibration occurs at high speeds. Do an off–
vehicle, two–plane dynamic balance first to correct any im-
balance in the tire and wheel assembly.
An on–vehicle finish balance will correct any brake drum,
rotor, or wheel cover imbalance. If balancing does not cor-
rect the high–speed vibration, or if the vibration occurs at
low speeds, runout is the probable cause.
Runout
Runout can be caused by the tire, the wheel, or the way
the wheel is attached to the vehicle. To investigate the pos-
sibility of wheel runout, refer to the following procedures
as well as the wheel runout diagnosis chart in this section:
1. If runout is suspected, measure the on–vehicle free
lateral and free radial runout of the tire and wheel
assembly. Refer to Section 2E, Tires and Wheels.
Both the free lateral and the free radial runout
should be less than 1.5 mm (0.06 inch). If either
measurement exceeds this number, proceed to
Step 2.
2. Mount the tire and the wheel on a dynamic balanc-
ing machine and remeasure the free lateral and the
free radial runout. Record the amount of the free
lateral and the free radial runout and the location of
the highest measurement. Refer to Section 2E,
Tires and Wheels. If the free radial or the free later-
al runout exceeds 1.3 mm (0.05 inch) at the tire
tread, proceed to Step 4.
3. Measure the wheel runout. Refer to Section 2E,
Tires and Wheels. If the wheel exceeds specifica-
tions, replace it.
4. Deflate the tire and match–mount the high radial
runout point of the tire to the low radial runout point
of the wheel. Reinflate the tire and mount it on the
dynamic balancing machine. Measure and record
the free radial and the free lateral runout and their
locations. In many cases, match mounting the tire
on the wheel will bring the tire and wheel assem-
bly’s free runout into an acceptable range of 1.3
mm (0.05 inch) or less.
5. If the free runout of the tire and wheel assembly is
1.3 mm (0.05 inch) or less when it was measured
off the vehicle, yet exceeds 1.3 mm (0.05 inch)
when measured on the vehicle, the attachment of
the tire and wheel assembly to the hub is the prob-
able cause of the vibration. Rotate the assembly’s
two wheel studs and recheck the runout. Refer
toSection 2E, Tires and Wheels. Several positions
may have to be tried to find the best location for the
studs.
6. If the tire and wheel assembly free runout cannot
be reduced to 1.3 mm (0.05 inch) or less, remove
the assembly.
1) Measure the wheel stud runout using a dial
indicator set with a magnetic base.
2) Zero the dial indicator set button on one stud.
3) Gently lift the set button off the stud. Rotate
the flange to position the next stud against the
dial indicator set.
4) Record the runout of all the studs. The dial in-
dicator should read zero when it is repositioned
on the first stud that was checked.
5) If the runout exceeds 0.76 mm (0.03 inch), the
hub or the hub and bearing assembly should
be replaced.
2B – 8IWHEEL ALIGNMENT
DAEWOO V–121 BL4
PRELIMINARY INSPECTION
ChecksAction
Check the tires for proper inflation pressures and normal
tread wear.Inflate the tires to the proper tire pressure. Replace the
tires as needed.
Check the wheel bearings for looseness.Tighten the axle nut to the proper specification. Replace
the strut wheel bearing as needed.
Check for loose ball joints and tie rod ends.Tighten the ball joints and the tie rods.
Check the runout of the wheels and the tires.Measure and correct the tire runout.
Check the vehicle trim heights.Correct the trim heights. Make the correction before ad-
justing the toe.
Check for loose rack and pinion mounting.Tighten the mounting brackets for the rack and pinion as-
sembly.
Check for improperly operating struts.Replace the strut assembly.
Check for loose control arms.Tighten the control arm attachment bolts. Replace the con-
trol arm bushings as needed.
FRONT TOE ADJUSTMENT
1. Disconnect the outer tie rods from the knuckle as-
semblies. Refer to Section 6C, Power Steering
Gear.
2. Turn the right and the left outer tie rods and the ad-
juster nuts to align the toe to 0.0 ± 0.10 degree.
3. Reconnect the outer tie rods to the knuckle assem-
blies. Refer to Section 6C, Power Steering Gear.
Notice : In this adjustment, the right and the left tie rods
must be equal in length, or the tires will wear unevenly.FRONT CAMBER AND CASTER
CHECK
The front camber and caster are not adjustable. Refer to
”Wheel Alignment Specifications” in this section. Jounce
the bumper three times before measuring the camber or
the caster in order to prevent an incorrect reading. If the
front camber or caster measurements deviate from the
specifications, locate and replace or repair any damaged,
loose, bent, dented, or worn suspension part. If the prob-
lem is body related, repair the body.
REAR CAMBER CHECK
The rear camber is not adjustable. Refer to ”Wheel Align-
ment Specifications” in this section. If the rear camber
deviates from the specification, locate the cause and cor-
rect it. If damaged, loose, bent, dented, or worn suspen-
sion parts are found, they should be repaired or replaced.
If the problem is body related, repair the body.
WHEEL ALIGNMENT 2B – 9
DAEWOO V–121 BL4
REAR TOE ADJUSTMENT
Adjustment Procedure
1. Perform a preliminary inspection before any at-
tempt is made to change or correct the wheel align-
ment factors. Refer to ”Preliminary Inspection” in
this section.
2. Loosen the nuts on the parallel link–to–crossmem-
ber bolts.
3. Rotate the parallel link adjustment bolts until the
preferred rear toe specification is obtained. Refer
to”Wheel Alignment Specifications” in this section
for preferred specifications.
4. Hold the parallel link adjustment bolts and tighten
the parallel link–to–crossmember nuts.
Tighten
Tighten the parallel link–to–crossmember nuts to 90 NSm
(66 lb–ft).
SECTION : 2C
FRONT SUSPENSION
CAUTION : Disconnect the negative battery cable before removing or installing any electrical unit or when a tool
or equipment could easily come in contact with exposed electrical terminals. Disconnecting this cable will help
prevent personal injury and damage to the vehicle. The ignition must also be in LOCK unless otherwise noted.
TABLE OF CONTENTS
SPECIFICATIONS2C–2 . . . . . . . . . . . . . . . . . . . . . . . . . .
General Specifications 2C–2. . . . . . . . . . . . . . . . . . . . .
Fastener Tightening Specifications 2C–2. . . . . . . . . . .
SPECIAL TOOLS2C–3 . . . . . . . . . . . . . . . . . . . . . . . . . . .
Special Tools Table 2C–3. . . . . . . . . . . . . . . . . . . . . . . .
DIAGNOSIS2C–5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Strut Dampener 2C–5. . . . . . . . . . . . . . . . . . . . . . . . . . .
Ball Joint and Knuckle 2C–6. . . . . . . . . . . . . . . . . . . . . .
Excessive Friction Check 2C–6. . . . . . . . . . . . . . . . . . .
COMPONENT LOCATOR2C–7 . . . . . . . . . . . . . . . . . . . .
Front Suspension 2C–7. . . . . . . . . . . . . . . . . . . . . . . . . .
MAINTENANCE AND REPAIR2C–9 . . . . . . . . . . . . . . .
ON–VEHICLE SERVICE 2C–9. . . . . . . . . . . . . . . . . . . . .
Stabilizer Shaft and Insulators 2C–9. . . . . . . . . . . . . . . Stabilizer Link 2C–10. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Knuckle Assembly 2C–10. . . . . . . . . . . . . . . . . . . . . . . .
Hub and Bearing 2C–13. . . . . . . . . . . . . . . . . . . . . . . . .
Control Arm 2C–14. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Strut Assembly 2C–16. . . . . . . . . . . . . . . . . . . . . . . . . . .
Crossmember Assembly 2C–18. . . . . . . . . . . . . . . . . . .
UNIT REPAIR 2C–21. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Ball Joint 2C–21. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Control Arm Bushings 2C–21. . . . . . . . . . . . . . . . . . . . .
Front Strut Assembly 2C–22. . . . . . . . . . . . . . . . . . . . . .
Knuckle 2C–23. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
GENERAL DESCRIPTION AND SYSTEM
OPERATION 2C–25 . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Front Suspension 2C–25. . . . . . . . . . . . . . . . . . . . . . . . .
2C – 6IFRONT SUSPENSION
DAEWOO V–121 BL4
BALL JOINT AND KNUCKLE
Ball Joint Inspection
1. Raise the front of the vehicle to allow the front sus-
pension to hang free.
2. Grasp the tire at the top and the bottom.
3. Move the top of the tire in an in–and–out motion.
4. Look for any horizontal movement of the knuckle
relative to the control arm.
5. Ball joints must be replaced under the following
conditions:
S The joint is loose.
S The ball seal is cut.
S The ball stud is disconnected from the knuckle.
S The ball stud is loose at the knuckle.
S The ball stud can be twisted in its socket with
finger pressure.
Ball Stud Inspection
Make sure to check the tightness of the ball stud in the
knuckle boss during each inspection of the ball joint. One
way to inspect the ball stud for wear is to shake the wheel
and feel for movement of the stud end at the knuckle boss.Another way to inspect the ball stud for wear is to check
the fastener torque at the pinch nut. A loose nut can indi-
cate a stressed stud or a hole in the knuckle boss.
Worn or damaged ball joints and knuckles must be re-
placed.
EXCESSIVE FRICTION CHECK
Use the following procedure to check for excessive friction
in the front suspension:
1. Enlist the help of another technician to lift up on the
front bumper, raising the vehicle as high as pos-
sible.
2. Slowly release the bumper, allowing the vehicle to
assume its normal trim height. See ”General Speci-
fications” in this section.
3. Measure the distance from the street level to the
center of the bumper.
4. Push down on the bumper, release slowly, and al-
low the vehicle to assume its normal trim height.
5. Measure the distance from the street level to the
center of the bumper.
6. The difference between the two measurements
should be less than 12.7 mm (0.5 inch). If the differ-
ence exceeds this limit, inspect the control arms,
the struts, and the ball joints for damage or wear.