GM Service Manual Online
For 1990-2009 cars only

Step

Action

Yes

No

DEFINITION: Any noise emitted from the front of the vehicle that is induced by vehicle speed or driving terrain as related to the front suspension.

1

Did you review the General Description and perform the necessary inspections?

Go to Step 2

Go to Symptoms - Suspension General Diagnosis

2

Note: Compare this vehicle to an identical vehicle in order to determine if the customer's concern is a normal operating characteristic of the vehicle.

Attempt to duplicate the noise. Road test the vehicle.

Is the front suspension noisy?

Go to Step 3

System OK

3

  1. Shift the transmission into Park.
  2. Turn the ignition off.
  3. Bounce the front of the vehicle in order to duplicate the noise.

Is the noise present?

Go to Step 4

Go to Step 5

4

  1. Bounce the front of the vehicle. Use J 39570 Chassis Ear in order to locate the source of the noise.
  2. Repair or replace the suspect components as necessary.

Did you complete the repair?

Go to Step 25

--

5

  1. Raise and support the vehicle. Refer to J 39570 .
  2. Inspect all of the front suspension components for any damage.

Are any components damaged?

Go to Step 6

Go to Step 7

6

Repair any damaged components.

Did you complete the repair?

Go to Step 25

--

7

  1. Inspect the tires for proper inflation. Refer to Vehicle Certification, Tire Placard, Anti-Theft, and Service Parts ID Label. Correct the tire inflation pressure as necessary.
  2. Inspect the tires for unusual wear. Refer to Tire Diagnosis - Irregular or Premature Wear.

Does either tire exhibit unusual tread wear?

Go to Step 8

Go to Step 10

8

  1. Rotate the tires. Refer to Tire Rotation.
  2. Road test the vehicle.

Is the noise now emitted from the rear of the vehicle?

Go to Step 9

Go to Step 10

9

Replace the tires that are causing the noise.

Did you complete the repair?

Go to Step 25

--

10

Ensure that the ball joints and steering linkage are lubricated, if applicable. Lubricate/replace as necessary.

Did you service any components?

Go to Step 25

Go to Step 11

11

Caution: Refer to Fastener Caution in the Preface section.

Ensure that all of the wheel nuts are tightened to the correct specification. Tighten as necessary. Refer to Fastener Tightening Specifications.

Did you tighten any wheel nuts?

Go to Step 25

Go to Step 12

12

Use your hands in order to push and pull the shock.

Is the shock loose?

Go to Step 13

Go to Step 15

13

  1. Inspect the shock module fasteners for the correct fastener tightening specification. Tighten as necessary. Refer to Fastener Tightening Specifications.
  2. Use your hand to push and pull the shock module.
  3. Is the shock module loose?

Go to Step 14

Go to Step 25

14

Replace the loose or worn shock module components. Refer to Shock, Shock Component, and/or Spring Replacement.

Did you complete the repair?

Go to Step 25

--

15

Use your hands in order to push and pull on the stabilizer shaft.

Is the stabilizer shaft loose?

Go to Step 16

Go to Step 20

16

  1. Inspect all of the stabilizer shaft fasteners. Tighten as necessary. Refer to Fastener Tightening Specifications.
  2. Use your hands in order to push and pull on the stabilizer shaft.

Is the stabilizer shaft loose?

Go to Step 17

Go to Step 25

17

Observe the location of the stabilizer shaft looseness.

Is the looseness observed at the stabilizer shaft links?

Go to Step 18

Go to Step 20

18

Replace the stabilizer shaft links. Refer to Stabilizer Shaft Link Replacement.

Did you complete the repair?

Go to Step 25

--

19

Replace the stabilizer shaft insulators and/or brackets. Refer to Stabilizer Shaft Insulator Replacement.

Did you complete the repair?

Go to Step 25

--

20

Inspect the control arms for looseness or movement.

Is any looseness or movement observed?

Go to Step 21

Go to Step 23

21

  1. Inspect the control arm fasteners for the correct fastener tightening specification. Refer to Fastener Tightening Specifications. Tighten as necessary.
  2. Inspect the control arm for looseness.

Is the control arm loose?

Go to Step 22

Go to Step 25

22

Replace any worn or loose control arm bushings. Refer to Lower Control Arm Replacement.

Did you complete the repair?

Go to Step 25

--

23

  1. Start the engine with the drive wheels off of the ground.
  2. Shift the transmission into Drive.
  3. Warning: Do not spin the drive wheels faster than 55 km/h (35 mph) as indicated by the speedometer. This limit is necessary because the speedometer indicates only one half of the actual wheel speed when one drive wheel is spinning and the other drive wheel is stopped. Personal injury and damage may result from high speed spinning.

    Note: This step will require the assistance of another person to maintain the drive train speed. Do not use the cruise control to maintain the drivetrain speed.

  4. Increase the drive wheel speed until the noise is at the most audible level.
  5. Note: Do not allow the J 39570 to contact any moving components.

  6. Use J 39570 in order to locate the source of the noise.

Does either wheel bearing exhibit noise?

Go to Step 24

Go to Step 8

24

Replace the wheel bearings. Refer to Front Wheel Bearing and Hub Replacement.

Did you complete the repair?

Go to Step 25

--

25

Operate the vehicle in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 3