STEERING, SUSPENSION, WHEELS AND TIRES 3-1
6F1
6F2
6G
6H
6K
3
7A1
7B1
7C1
7D
7E
7F
8A
8B
8C
8D
8E
9
10
10A
10B
SECTION 3
STEERING, SUSPENSION, WHEELS AND TIRES
DIAGNOSIS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-2
FRONT END ALIGNMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Section 3A
MANUAL RACK AND PINION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Section 3B
ELECTRICAL POWER STEERING (P/S) SYSTEM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Section 3B1
STEERING WHEEL AND COLUMN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Section 3C
FRONT SUSPENSION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Section 3D
REAR SUSPENSION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Section 3E
WHEELS AND TIRES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Section 3F
CONTENTS
DIAGNOSIS ........................................................ 3-2
GENERAL DIAGNOSIS .................................. 3-2
DIAGNOSIS TABLE ........................................ 3-2
TIRE DIAGNOSIS ........................................... 3-5
IRREGULAR AND/OR PREMATURE
WEAR.......................................................... 3-5WEAR INDICATORS .................................. 3-5
RADIAL TIRE WADDLE.............................. 3-6
RADIAL TIRE LEAD.................................... 3-7
VIBRATION DIAGNOSIS................................ 3-7
3-2 STEERING, SUSPENSION, WHEELS AND TIRES
DIAGNOSIS
GENERAL DIAGNOSIS
Since the problems in steering, suspension, wheels and tires involve several systems, they must all be consid-
ered when diagnosing a complaint. To avoid using the wrong symptom, always road test the vehicle first. Pro-
ceed with the following preliminary inspection and correct any defects which are found.
1) Inspect tires for proper pressure and uneven wear.
2) Raise vehicle on a hoist and inspect front and rear suspension and steering system for loose or damaged
parts.
3) Spin front wheels. Inspect for out-of-round tires, out-of-balance tires, bent rims, loosen and/or rough wheel
bearings.
DIAGNOSIS TABLE
Condition Possible Cause Correction
Vehicle Pulls (Leads)
Mismatched or uneven tires Replace tire.
Tires not adequately inflated Adjust tire pressure.
Broken or sagging springs Replace spring.
Radial tire lateral force Replace tire.
Disturbed front end alignment Check and adjust front end align-
ment.
Brake dragging in one road wheel Repair brake.
Loose, bent or broken front or rear suspension
partsTighten or replace suspension
parts.
Abnormal or
Excessive Tire WearSagging or broken spring Replace spring.
Tire out of balance Adjust balance or replace tire.
Disturbed front end alignment Check and adjust front end align-
ment.
Faulty strut (shock absorber) Replace strut.
Hard driving Replace tire.
Overloaded vehicle Replace tire.
Not rotating tire Replace or rotate tire.
Worn or loose wheel bearing Replace wheel bearing.
Wobbly wheel or tire Replace wheel or tire.
Tires not adequately inflated Adjust tire pressure.
Wheel Tramp
Blister or bump on tire Replace tire.
Improper strut (shock absorber) action Replace strut.
Shimmy, Shake or
VibrationTire or wheel out of balance Balance wheels or replace tire and/
or wheel.
Loosen wheel bearings Replace wheel bearing.
Worn tie rod ends Replace tie rod end.
Worn lower ball joints Replace front suspension arm.
Excessive wheel runout Repair or replace wheel and/or tire.
Blister or bump on tire Replace tire.
Excessively loaded radial runout of tire/wheel
assemblyReplace tire or wheel.
Disturbed front end alignment Check and adjust front end align-
ment.
Loose or worn steering linkage Tighten or replace steering linkage.
Loose steering gear case bolts Tighten case bolts.
STEERING, SUSPENSION, WHEELS AND TIRES 3-3
Hard Steering
Tire not adequately inflated Inflate tires to proper pressure.
Malfunction of power steering system Check and correct.
Bind in tie rod end ball studs or lower ball joints Replace tie rod end or front sus-
pension arm.
Disturbed front end alignment Check and adjust front end align-
ment.
Rack and pinion adjustment Check and adjust rack and pinion
torque.
Bind in steering column Repair or replace.
Too Much Play in
SteeringWheel bearings worn Replace.
Loose steering gear case bolts Tighten.
Rack and pinion adjustments Check and adjust rack and pinion
torque.
Worn steering shaft joints Replace joint.
Worn tie rod ends or tie rod inside ball joints Replace tie rod end or tie rod.
Worn lower ball joints Replace front suspension control
arm.
Poor Returnability
Bind in tie rod end ball studs Replace tie rod end.
Bind in ball joints Replace.
Bind in steering column Repair or replace.
Poorly lubricated rack and pinion Check, repair or lubricate rack and
pinion.
Disturbed front end alignment Check and adjust front end align-
ment.
Rack and pinion adjustment Check and adjust rack and pinion
torque.
Tires not adequately inflated Adjust tire pressure.
Rack and Pinion Noise
(Rattle or Chuckle)Loose steering gear case bolts Tighten.
Worn rack bush Replace.
Rack and pinion adjustment Check and adjust rack and pinion
torque.
Abnormal Noise,
Front EndWorn, sticky or loose tie rod ends, lower ball
joints, tie rod inside ball joints or drive shaft
jointsReplace tie rod end, suspension
arm, tie rod or drive shaft joint.
Damaged struts or mountings Repair or replace.
Worn suspension arm bushings Replace.
Loose stabilizer bar Tighten bolts or nuts, replace
bushes.
Loose wheel nuts Tighten wheel nuts.
Loose suspension bolts or nuts Tighten suspension bolts or nuts.
Broken or otherwise damaged wheel bearings Replace.
Broken suspension springs Replace.
Poorly lubricated or worn strut bearings Replace strut bearing. Condition Possible Cause Correction
3-4 STEERING, SUSPENSION, WHEELS AND TIRES
Wander or Poor
Steering StabilityMismatched or uneven tires Replace or inflate tires to proper
pressure.
Loosen ball joints and tie rod ends Replace suspension arm or tie rod
end.
Faulty struts or mountings Replace strut or repair mounting.
Loose stabilizer bar Tighten or replace stabilizer bar or
bush.
Broken or sagging springs Replace spring.
Rack and pinion adjustment Check and adjust rack and pinion
torque.
Disturbed front end alignment Check and adjust front end align-
ment.
Erratic Steering When
BrakingWorn wheel bearings Replace.
Broken or sagging springs Replace coil spring.
Wheel tires are inflated unequally Inflate tires to proper pressure.
Disturbed front end alignment Check and adjust front end align-
ment.
Brakes not working in unison Check and adjustment brake sys-
tem.
Leaking wheel cylinder or caliper Repair or replace wheel cylinder or
caliper.
Warped discs Replace brake disc.
Badly worn brake linings Replace brake shoe lining.
Drum is out of round in some brakes Replace brake drum.
Defective wheel cylinders Replace or repair wheel cylinder.
Low or Uneven Trim
Height
NOTE:
See NOTE *1.Broken or sagging springs Replace.
Over loaded Check loading.
Incorrect springs Replace.
Ride Too Soft
Faulty struts (shock absorber) Replace strut.
Suspension Bottoms
Overloaded Check loading.
Faulty struts (shock absorber) Replace strut.
Incorrect, broken or sagging springs Replace.
Body Leans or Sways
in CornersLoose stabilizer bar Tighten stabilizer bar bolts or nuts,
or replace bushes.
Faulty struts (shock absorbers) or mountings Replace strut or tighten mounting.
Broken or sagging springs Replace.
Overloaded Check loading.
Cupped Tires
Front struts defective Replace.
Worn wheel bearings Replace.
Excessive tire or wheel run-out Replace tire or wheel disc.
Worn ball joints Replace front suspension arm.
Tire out of balance Adjust tire balance. Condition Possible Cause Correction
STEERING, SUSPENSION, WHEELS AND TIRES 3-5
TIRE DIAGNOSIS
IRREGULAR AND/OR PREMATURE WEAR
Irregular and premature wear has many causes. Some of them
are: incorrect inflation pressures, lack of tire rotation, driving hab-
its, improper alignment.
If the following conditions are noted, rotation is necessary:
Front tire wear is different from rear.
Uneven wear exists across the tread of any tire.
Front tire wear is unequal between the right and left.
Rear tire wear is unequal between the right and left.
There is cupping, flat spotting, etc.
A wheel alignment check is necessary if following conditions are
noted:
Front tire wear is unequal between the right and left.
Wear is uneven across the tread of any front tire.
Front tire treads have scuffed appearance with “feather”
edges on one side of tread ribs or blocks.
WEAR INDICATORS
Original equipment tires have built-in tread wear indicators (1) to
show when they need replacement.
These indicators (1) will appear as 12 mm (0.47 in) wide bands
when the tire tread depth becomes 1.6 mm (0.063 in).
When the indicators (1) appear in 3 or more grooves at 6 loca-
tions, tire replacement is recommended.NOTE:
*1: Right-to-left trim height (“H”) difference should be
within 15 mm (0.6 in.) with curb weight. (same with rear
side.)
“H”
[A] : Hard Cornering, under inflation or lack of tire rotation
[B] : Incorrect wheel alignment, tire construction not uniform or wheel heavy acceleration
3-6 STEERING, SUSPENSION, WHEELS AND TIRES
RADIAL TIRE WADDLE
Waddle is side to side movement at the front and/or rear of the
vehicle. It is caused by the steel belt not being straight within the
tire. It is most noticeable at a low speed, 8 to 48 kph (5 to 30
mph).
It is possible to locate the faulty tire by road testing the vehicle. If
it is on the rear, the rear end of the vehicle shakes from side to
side or “waddles”. To the driver in the seat, it feels as though
someone is pushing on the side of vehicle.
If the faulty tire is on the front, waddling is more visual. The front
sheet metal appears to be moving back and forth and the driver
feels as though he is at the pivot point in vehicle.
Waddle can be quickly diagnosed by using Tire Problem Detector
(TPD) and following the equipment manufacture’s recommenda-
tions.
If TPD is not available, an alternative method of substituting
known-good tire/wheel assemblies can be used as follows,
although it takes a longer time.
1) Ride vehicle to determine whether the front or rear waddles.
2) Install tires and wheels that are known to be good (on similar vehicle) in place of those on waddling end of
vehicle. If waddling end cannot be identified, substitute rear ones.
3) Road test again. If improvement is noted, reinstall originals one at a time till waddle causal tire is found. If no
improvement is noted, install known-good tires in place of all four. Then reinstall originals in the same man-
ner as above.
EQUIPMENT MANUFACTURE’S RECOMMENDATIONS
In flate tires to recommended pressure
Road test vehicle on level unrowned road in both directions
Switch front tires side to side and road test again
Lead corrected,
if roughness results, replace tiresLeads in same directionLeads reverses direction
Put tires back in original position
and check alignmentInstall a known-good tire on one front side
Lead remains install a known-good
tire in place of other front tire
Lead remains known-good tires are not goodLead corrected replace tire
Lead corrected replace tire
STEERING, SUSPENSION, WHEELS AND TIRES 3-7
RADIAL TIRE LEAD
“Lead” is the deviation of the vehicle from a straight path on a level rod even with no pressure on the steering
wheel.
Lead is usually caused by:
Incorrect alignment.
Uneven brake adjustment.
Tire construction.
The way in which a tire is built can produce lead in a vehicle. An example of this is placement of the belt. Off
center belts on radial tires can cause the tire to develop a side force while rolling straight down the road. If one
side of the tire has a little larger diameter than the other, the tire will tend to roll to one side. This will develop a
side force which can produce vehicle lead.
The procedure in above figure (Lead Diagnosis) should be used to make sure that front alignment is not mis-
taken for tire lead.
Part of the lead diagnosis procedure is different from the proper tire rotation pattern currently in the owner
and service manuals. If a medium to high mileage tire is moved to the other side of the vehicle, be sure to
check that ride roughness has not developed
Rear tires will not cause lead.
VIBRATION DIAGNOSIS
Wheel unbalance causes most of the highway speed vibration problems. If a vibration remains after dynamic
balancing, its possible causes are as follows.
Tire runout.
Wheel runout.
Tire stiffness variation.
Measuring tire and/or wheel free runout will uncover only part of the problem. All three causes, known as loaded
radial runout, must be checked by using a Tire Problem Detector (TPD). If TPD is not available, alternative
method of substituting known-good tire and wheel assemblies on the problem vehicle can be used, although it
takes a longer time.
[A] : Tire out of round 1. Smooth road
[B] : Tire stiffness variation 2. Suspension movement (loaded runout)
[C] : Rim bent or out of round
3-8 STEERING, SUSPENSION, WHEELS AND TIRES