Squeak or grunt-noise from the front suspension, occurs more in cold ambient temperatures-more noticeable over rough roads or when turning

Front stabilizer bar

Under these conditions, the noise is acceptable.

Clunk-noise from the front suspension, occurs in and out of turns

Loose front struts or shocks

Inspect for loose nuts or bolts.

Tighten to specifications.

See page SS-26.

Clunk-noise from the rear suspension, occurs when shifting from reverse to drive

Loose rear suspension components

Inspect for loose or damaged rear suspension components.

Repair or install new components as necessary.

See page SS-47.

Click or pop-noise from the front suspension-more noticeable over rough roads or over bumps

Worn or damaged ball joints

Install new lower arm as necessary.

See page SS-34.

Click or pop-noise occurs when vehicle is turning

Worn or damaged ball joints

Install new lower arm as necessary.

See page SS-34.

Click or snap-occurs when accelerating around a corner

Damaged or worn Birfield joint

Repair or install a new Birfied joint as necessary.

See DS group - driveshaft.

Front suspension noise-a squeak, creak or rattle noise-occurs mostly over bumps or rough roads

Steering components

Loose or bent front struts or shock absorbers

Damaged spring or spring mounts

Damaged or worn arm bushings

Worn or damaged stabilizer bar bushing or links

Go to detailed test A.

See page SS-11.

Groaning or grinding-noise from the front strut, occurs when driving on bumpy roads or turning the vehicle

Uneven seating surface between the insulator and panel by the burrs around the strut insulator mounting bolts and the insulator boltes mounting holes

Repair or install a new parts as necessary.

See page SS-29.

Rear suspension noise - a squeak, creak or rattle noise - occurs mostly over bumps or rough roads

Loose or bent rear shock absorbers

Damaged spring or spring mounts

Damaged or worn control arm bushings

Go to detailed test B.

See page SS-12.

Shudder-occurs during acceleration from a slow speed or stop

Rear axle assembly mispositioned

Damaged or worn front suspension components

Check the axle mounts and Rear suspension the rear suspension for damage or wear. Repair as necessary.

Check for a loose stabilizer bar, damaged or loose strut/strut bushings or loose or worn ball joints. Inspect the steering linkage for wear or damage. Repair or Install new components as necessary.

Shimmy-most noticeable on coast/deceleration-also hard steering condition

Excessive positive caster

Check the caster alignment angle.

Correct as necessary.

See page SS-70.

Tire noise-hum/moan at constant speeds

Abnormal wear patterns

Spin the tire and Check for tire wear. Install a new tire as necessary. Inspect for damaged/worn suspension components. Carry out wheel alignment.

See page SS-68, SS-72.

Tire noise-noise tone lowers as the vehicle speed is lowered

Out-of-balance tire

Balance the tire and road test. Install a new tire as necessary.

See page SS-72.

Tire noise - ticking noise, change with speed

Nail puncture or stone in tire tread

Inspect the tire. Repair as necessary.

See page SS-72.

Wheel and tire-vibration and noise concern is directly related to vehicle speed and is not affected by acceleration, coasting or decelerating

Damaged or worn tire

Go to detailed test C.

See page SS-13.

Tire wobble or shudder - occurs at lower speeds

Damaged wheel bearings

Spin the tire and check for abnormal wheel bearing play or roughness. Adjust or Install new wheel bearings as necessary.

See DS group - front/rear axle.

Damaged wheel

Inspect the wheel for damage. Install a new wheel as necessary.

See page SS-72.

Damaged or worn suspension components

Inspect the suspension components for wear or damage. Repair as necessary.

See page SS-26.

Loosen wheel nuts

Check the wheel nuts.

Tighten to specification.

See page SS-71.

Damaged or uneven tire wear

Spin the tire and Check for abnormal tire wear or damage. Install a new tire as necessary.

See page SS-72.

Tire shimmy or shake - occurs at lower speeds

Wheel/tire out of balance

See page SS-70.

Uneven tire wear

Check for abnormal tire wear. Install a new tire as necessary.

See page SS-72.

Excessive radial runout of wheel or tire

Carry out a radial runout test of the wheel and tire.

Install a new tire as necessary.

See page SS-70.

Worn or damaged wheel studs or elongate stud holes

Inspect the wheel studs and wheels.

Install new components as necessary.

See page SS-72.

Excessive lateral runout of the wheel or tire

Carry out a lateral runout test of the wheel and tire.

Check the wheel, tire and hub. Repair or Install new components as necessary.

See page SS-70.

Foreign materal between the brake disc and hub.

Clean the mounting surfaces of the brake disc and hub.

See DS group - front/rear axle.

High speed shake or shimmy-occurs at high speeds

Excessive wheel hub runout

Damaged or worn tires

Damaged or worn wheel bearings

Worn or damaged suspension or steering linkage

Brake disc or drum imbalance

Go to detailed test D.

See page SS-16.

Drift left or right

Tires

Steering linkage

Alignment

Base brake system

Go to detailed test E.

See page SS-18.

Steering wheel

Alignment

Steering linkage

Front lower arm ball joint

Go to detailed test F.

See page SS-19.

Tracks incorrectly

Rear suspension

Caster

Go to detailed test G.

See page SS-20.

Rough ride

Front strut and spring assembly

Rear shock absor and spring assembly

Go to detailed test H.

See page SS-21.

Excessive noise

Front or rear stabilizer bar components

Springs

Suspension components

Shock absorbers

Go to detailed test I.

See page SS-21.

Incorrect tire wear

Tire or unbalanced wheels

Tire inflation

Strut

Alignment

Go to detailed test J.

See page SS-22.

Vibration

Wheel/tire

Front wheel drivshaft(s)

Steering system

Strut and spring assembly

Spring and strut mounting

Front lower arm ball joint

Front lower arm mounting bolt bushing

Stabilizer bar bushings

Wheel hubs and bearing

Rear suspension arms and bushings

Go to detailed test K.

See page SS-22.

Vehicle leans

Tire/wheel

Vehicle load

Suspension components

Incorrect ride height

Inflate tires to specification.

Redistribute the load as necessary.

Visually inspect the suspention system.

Correct the ride height as necessary.

Poor returnability

High knuckle rotating torque

Alignment

Go to detailed test E.

See page SS-18.

ROAD TEST THE VEHICLE

INSPECT THE STEERING SYSTEM

FRONT SHOCK ABSORBER/STRUT CHECK

CHECK THE FRONT SPRINGS

Check the front spring and front spring mounts/brackets for wear or damage

● Are the front springs or spring mounts/brackets worn or damaged ?

⇒ YES

Repair or Install new components as necessary. Test the system for normal operation.

⇒ NO

Go toA5.

CHECK THE STABILIZER BAR

ROAD TEST THE VEHICLE

REAR SHOCK ABSORBER/STRUT CHECK

CHECK THE REAR SPRINGS

Check the rear springs and rear spring mounts/brackets for wear or damage.

● Are the rear springs or spring mounts/brackets worn or damaged ?

⇒ YES

Repair or Install new components as necessary. Test the system for normal operation.

⇒ NO

Go toB4.

CHECK THE TRAILING ARMS

ROAD TEST THE VEHICLE

During the road test, if the vibration can be eliminated by placing the vehicle in neutral or is affected by the speed of the engine, the cause is not the wheels or tires.

● Is there a vibration and noise ?

⇒ YES

Go toC2.

⇒ NO

The wheel and tires are OK. Conduct a diagnosis on other suspect systems.

CHECK THE FRONT WHEEL BEARINGS

Check the front wheel bearings.

Refer to Wheel Bearing Check (See DS group - front axle).

● Are the wheel bearings OK ?

⇒ YES

Go toC3.

⇒ NO

Inspect the wheel bearings. Adjust or Repair as necessary. Test the system for normal operation.

INSPECT THE TIRES

TIRE ROTATION DIAGNOSIS

RADIAL RUNOUT CHECK ON THE TIRE

Measure the radial runout of the wheel and tire assembly. A typical specification for total radial runout is 1.15mm (0.059 inch).

● Is the radial runout within specifications ?

⇒ YES

Go toC8.

⇒ NO

Go toC6.

RADIAL RUNOUT CHECK ON THE WHEEL

Measure the radial runout of the wheel. A typical specification for total radial runout is 1.14mm (0.045 inch.).

● Is the radial runout within specifications ?

⇒ YES

Install a new tire. Test the system for normal operation.

⇒ NO

Go toC7.

CHECK THE HUB/BRAKE DISC OR DRUM PILOT RUNOUT OR BOLT CIRCLE RUNOUT

Measure the pilot or bolt circle runout. A typical specification for radial runout is :

● pilot runout - less than 0.15mm (0.006 inch.)

● bolt circle runout - less than 0.38 mm (0.015 inch.)

● Is the radial runout within specification ?

⇒ YES

Install a new wheel. Test the system for normal operation.

⇒ NO

Repair or Install new components as necessary. See page SS-26 for the front suspension or SS-47 for the rear suspension.

LATERAL RUNOUT CHECK ON THE TIRE

Measure the lateral runout of the wheel and tire assembly. A typical specification for total lateral runout is 2.5mm (0.098 inch).

● Is the lateral runout within specifications ?

⇒ YES

Wheel and tires are OK. Conduct diagnosis on other suspect systems.

⇒ NO

Go toC9.

LATERAL RUNOUT CHECK ON THE WHEEL

Measure the lateral runout of the wheel. A typical specification for total radial runout is 1.2mm (0.047 inch.)

● Is the lateral runout within specifications ?

⇒ YES

Install a new tire. Test the system for normal operation.

⇒ NO

Go toC10.

CHECK THE FLANGE FACE LATERAL RUNOUT

Measure the flange face lateral runout. A typical specification for lateral runout is :

● hub/brake disc - less than 0.13mm (0.005 inch)

● Is the lateral runout within specifications ?

⇒ YES

Install a new wheel. Test the system for normal operation.

⇒ NO

Repair or Install new components as necessary. See page SS-26 for the front suspension or SS-47 for the rear suspension.

CHECK FOR FRONT WHEEL BEARING ROUGHNESS

CHECK THE END PLAY OF THE FRONT WHEEL BEARINGS

Check the end play of the front wheel bearings.

● Is the end play OK ?

⇒ YES

Go toD3.

⇒ NO

Adjust or Repair as necessary. Test the system for normal operation.

MEASURE THE LATERAL RUNOUT AND THE RADIAL RUNOUT OF THE FRONT WHEELS ON THE VEHICLE

Measure the lateral runout and the radial runout of the front wheels on the vehicle. Go to detailed test C.

● Are the measurements within specifications ?

⇒ YES

Go toD4.

⇒ NO

Install new wheels as necessary and Balance the assembly. Test the system for normal operation.

MEASURE THE LATERAL RUNOUT OF THE FRONT TIRES ON THE VEHICLE

Measure the lateral runout of the front tires on the vehicle. Go to detailed test C.

● Is the runout within specifications ?

⇒ YES

Go toD5.

⇒ NO

Install new tires as necessary and Balance the assembly. Test the system for normal operation.

MEASURE THE RADIAL RUNOUT OF THE FRONT TIRES ON THE VEHICLE

Measure the radial runout of the front tires on the vehicle. Go to detailed test C.

● Is the runout within specifications ?

⇒ YES

Balance the front wheel and tire assemblies. If any tire cannot be balanced, Install a new tire. Test the system for normal operation.

⇒ NO

Go toD6.

MATCH MOUNT THE TIRE AND WHEEL ASSEMBLY

Mark the high runout location on the tire and also on the wheel. Break the assembly down and rotate the tire 180 degrees (halfway around) on the wheel. Inflate the tire and measure the radial runout.

● Is the runout within specifications ?

⇒ YES

Balance the assembly. Test the system for normal operation.

⇒ NO

If the high spot is not within 101.6mm (4 inches) of the first high spot on the tire, Go toD7.

MEASURE THE WHEEL FLANGE RUNOUT

Dismount the tire and mount the wheel on a wheel balancer. Measure the runout on both wheel flanges. Go to detailed test C

● Is the runout within specifications ?

⇒ YES

Locate and Mark the low spot on the wheel. Install the tire, matching the high spot on the tire with the low spot on the wheel. Balance the assembly. Test the system for normal operation. If the condition persists, Go toD8.

⇒ NO

Install a new wheel. Check the runout on the new wheel. If the new wheel is within limits, locate and Mark the low spot. Install the tire, matching the high spot on the tire with the low spot on the wheel. Balance the assembly. Test the system for normal operation. If the condition persists, Go toD8.

CHECK FOR VIBRATION FROM THE FRONT OF THE VEHICLE

Spin the front wheel and tire assemblies with a wheel balancer while the vehicle is raised on a hoist. Feel for vibration in the front fender or while seated in the vehicle.

● Is the vibration persent ?

⇒ YES

Substitute known good wheel and tire assemblies as necessary.

Test the system for normal operation.

⇒ NO

Check the driveline components. Test the system for normal operation.

CHECK THE TIRES

Inspect the tires for excessive wear or damage.

● Are the tires excessively worn or damaged ?

⇒ YES

Install new tires.

⇒ NO

Go toE2.

CHECK THE STEERING LINKAGE

CHECK THE VEHICLE ALIGNMENT

BRAKE DRAG DIAGNOSIS

Apply the brakes while driving.

● Does drift or pull occur when the brakes are applied ?

⇒ YES

See BR group - specification.

⇒ NO

If the steering wheel is in the center, the vehicle is OK.

If the steering wheel is off-center, Go to Detailed TestF.

CHECK THE CLEAR VISION

Place the vehicle on an alignment rack.

● Is the clear vision within specification ?

⇒ YES

Go toF2.

⇒ NO

Adjust the clear vision to specification.

INSPECT THE STEERING COMPONENTS

CHECK THE CASTER

Place the vehicle on an alignment rack.

● Is the caster within specification ?

⇒ YES

Go toG2.

⇒NO

Replace bent or damaged parts.

CHECK THE REAR SUSPENSION

CHECK THE FRONT SHOCK ABSORBER

CHECK THE REAR SHOCK ABSORBERS

Inspect the rear shock absorbers for oil leaks or damage.

● Are the rear shock absorbers leaking ?

⇒ YES

Install new rear shock absorbers.

See page SS-50 (rear strut assembly).

⇒ NO

The vehicle is OK. Go toTROUBLESHOOTING.

INSPECT THE SUSPENSION

INSPECT THE SPRING AND TORSION BARS

Inspect the springs and stabilizer bars for damage.

● Are the spring or stabilizer bars damaged ?

⇒ YES

Install new spring and/or stabilizer bars.

See page SS-44 and SS-67 (front/rear stabilizer bars).

⇒ NO

Go toI3.

INSPECT THE FRONT SUSPENSION

Inspect the front suspension components for excessive wear or damage.

● Are the front suspension components worn or damaged ?

⇒ YES

Install new front suspension components.

See page SS-26 (front suspension).

⇒ NO

The vehicle is OK. Go toTROUBLESHOOTING.

INSPECT THE TIRES

UNEVEN TIRE WEAR

Inspect the tires for a feathering pattern.

● Do the tires have a feathering pattern ?

⇒ YES

Align the vehicle. Install new tires if badly worn.

⇒ NO

Go toJ3.

CHECK FOR CUPPED TIRE

Inspect the tires for cupping or dishing.

● Are the tires cupped or dished ?

⇒ YES

Balance and Rotate the tires.

⇒ NO

The vehicle is OK. Go toTROUBLESHOOTING.

ROAD TEST

Accelerate the vehicle to the speed at which the customer indicated the vibration occured.

● Is the vibration present ?

⇒ YES

Go toK2.

⇒ NO

The vehicle is OK. Go toTROUBLESHOOTING.

INSPECT THE TIRES

INSPECT THE WHEEL BEARINGS

Spin the tires by hand to check for wheel bearing rougness.

● Is the front wheel bearing OK ?

⇒ YES

Go toK4.

⇒ NO

Install new front wheel bearings as necessary.

See Ds group - front axle.

TIRE/WHEEL BALANCE

Check the tire/wheel balance.

● Are the tires balanced ?

⇒ YES

Go toK5.

⇒ NO

Balance the tires and wheels as necessary.

MEASURE THE RUNOUTS

For each wheel position measure, locate and mark the following items.

See page SS-70 (wheel/tire).

- High point of the tire/wheel assembly total radial runout

- High point of the wheel radial runout

- High point of the wheel lateral runout

● Are the runouts as specified ?

⇒ YES

Go toK7.

⇒ NO

Go toK6.

SUBSTITUTE THE WHEELS AND TIRE

Rapid wear at the center

Rapid wear at both shoulders

Wear at one shoulder

Partial wear

Feathered edge

Wear pattern