Noise Diagnosis - Front Suspension. Buick GL7 (Export) 2000

For 1990-2009 cars

Step | Action | Value | 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 | Important: It may be necessary to compare this vehicle to a identical vehicle to determine if the customer's complaint a normal operating characteristic of the vehicle. Attempt to duplicate the noise. Road test the vehicle. Is there an abnormal noise present? | -- | Go to Step 2 | System OK

2

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 heard?

--

Go to Step 3

Go to Step 4

3

1. Bounce the front of the vehicle. Use a stethoscope in order to locate the source of the noise.
2. Repair or replace the suspect component(s) as necessary.

Has the repair been performed.

--

Go to Step 1

--

4

1. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
2. Inspect all of the front suspension components for any damage.

Are any components damaged?

--

Go to Step 5

Go to Step 6

5 | Repair any damaged components. Has the repair been performed? | -- | Go to Step 1 | --

6

1. Inspect the tires for proper inflation. Refer to Tire Inflation Pressure Specifications in Maintenance and Lubrication. Correct the tire inflation pressure as necessary.
2. Inspect the tires for unusual wear. Refer to Tire Diagnosis - Irregular or Premature Wear in Tires and Wheels.

Does either tire exhibit unusual tread wear?

--

Go to Step 7

Go to Step 9

7

1. Rotate the tires. Refer to Tire Rotation in Tires and Wheels.
2. Road test the vehicle.

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

--

Go to Step 8

Go to Step 9

8 | Replace the tire(s) that are causing the noise. Has the repair been performed. | -- | Go to Step 1 | --
9 | Ensure that the ball joints and steering linkage are lubricated (if applicable). Lubricate/replace as necessary. Did you service any components? | -- | Go to Step 1 | Go to Step 10
10 | Ensure that all of the wheel nuts are tightened to the correct specification. Tighten as necessary. Refer to Fastener Tightening Specifications in Tires and Wheels. Did you tighten any wheel nuts? | -- | Go to Step 1 | Go to Step 11
11 | Use your hands in order to push and pull the strut. Is the strut loose? | -- | Go to Step 12 | Go to Step 14

12

1. Inspect the strut fasteners for the correct fastener tightening specification. Tighten as necessary. Refer to Fastener Tightening Specifications in Front Suspension.
2. Use your hand to push and pull the strut.

Is the strut loose?

--

Go to Step 14

Go to Step 1

13 | Replace the loose or worn strut components. Refer to Strut, Strut Component, and Spring Replacement in Front Suspension. Has the repair been performed? | -- | Go to Step 1 | --
14 | Use your hands in order to push and pull on the stabilizer shaft. Is the stabilizer shaft loose? | -- | Go to Step 15 | Go to Step 19

15

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

Is the stabilizer shaft loose?

--

Go to Step 18

Go to Step 1

16 | Observe the location of the stabilizer shaft looseness. Is the looseness observed at the stabilizer shaft links? | -- | Go to Step 17 | Go to Step 20
17 | Replace the stabilizer shaft link(s). Refer to Stabilizer Shaft Link Replacement in Front Suspension. Has the repair been performed? | -- | Go to Step 1 | --
18 | Replace the stabilizer shaft insulator(s) and/or bracket(s). Refer to Stabilizer Shaft Insulator Replacement in Front Suspension. Has the repair been performed? | -- | Go to Step 1 | --
19 | Inspect the control arms for looseness or movement. Is any looseness or movement observed? | -- | Go to Step 20 | Go to Step 22

20

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

Is the control arm loose?

--

Go to Step 21

Go to Step 1

21 | Replace any worn or loose control arm bushings. Refer to Front Lower Control Arm Bushing Replacement in Front Suspension. Has the repair been performed? | -- | Go to Step 1 | --

22

1. Start the engine with the drive wheels off of the ground.
2. Shift the transmission into DRIVE.

Caution: 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.

Important: 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.

3. Increase the drive wheel speed until the noise is at the most audible level.

Important: Do not allow the stethoscope to contact any moving components.

4. Use a stethoscope in order to locate the source of the noise.

Does either wheel bearing exhibit noise?

--

Go to Step 23

Go to Step 7

23 | Replace the wheel bearing(s). Refer to Front Wheel Bearing and Hub Replacement in Front Suspension. Has the repair been performed? | -- | Go to Step 1 | --