GM Service Manual Online
For 1990-2009 cars only

Noise Diagnosis - Front Suspension

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 system descriptions and perform the necessary Inspections?

Go to Step 2

Go to Symptoms - Suspension General Diagnosis

2

Attempt to duplicate the condition. Road test the vehicle.

Did you duplicate the condition?

Go to Step 3

System OK

3

Is the noise reactive to vehicle load or speed?

Go to Step 4

Go to Step 7

4

Inspect the tires for the following condition:

    • Proper tire inflation and adjust as necessary--Refer to Tire and Wheel Specifications.
    • Unusual tire wear--Refer to Tire Diagnosis - Irregular or Premature Wear.
    •  Inspect the wheel nuts for looseness and tighten as necessary. Refer to Fastener Tightening Specifications.

Did you find and correct the condition?

Go to Step 14

Go to Step 5

5

Inspect the front wheel bearings. Refer to Wheel Bearings Diagnosis.

Did you find and correct the condition?

Go to Step 14

Go to Step 6

6

Inspect for front axle or transaxle noises.

    • For vehicles equipped with the 6T40/6T45 transmission, refer to Symptoms - Automatic Transmission.
    • For vehicles equipped with the AF33-5 transmission, refer to Symptoms - Automatic Transmission.

Did you find and correct the condition?

Go to Step 14

Go to Step 7

7

Bounce the front of the vehicle in order to duplicate the noise.

Did you duplicate the noise?

Go to Step 8

Go to Step 9

8

  1. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle.
  2. Inspect the front suspension components for looseness. Refer to Fastener Tightening Specifications.
  3. Inspect the front suspension components for damage and repair as necessary.

Did you find and correct the condition?

Go to Step 14

Go to Step 9

9

  1. Install the J 39570 Chassis Ear or equivalent.
  2. Bounce the front of the vehicle, using the J 39570 or equivalent in order to locate the source of the noise. If necessary road test the vehicle.
  3. Repair or replace any damaged components as necessary.

Did you find and correct the condition?

Go to Step 14

Go to Step 10

10

Inspect the ball joints and steering components for the following conditions.

    •  Lack of lubrication where applicable
    •  Looseness in the ball joints--Refer to Ball Joint Inspection.
    • Looseness in the tie rods--Refer to Steering Linkage Outer Tie Rod Replacement.

Did you find and correct the condition?

Go to Step 14

Go to Step 11

11

Inspect for damaged shock absorbers. Refer to Suspension Strut and Shock Absorber Testing - On Vehicle.

Did you find and correct the condition?

Go to Step 14

Go to Step 12

12

Inspect the front stabilizer shaft and stabilizer shaft links for damage and repair as necessary. Refer to Stabilizer Shaft Replacement.

Did you find and correct the condition?

Go to Step 14

Go to Step 13

13

Inspect for control arm damage and repair as necessary. Refer to Lower Control Arm Replacement.

Did you find and correct the condition?

Go to Step 14

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14

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 3