Ford F150 Pickup. Instruction - part 1797

11. Inspect for damaged shock absorbers. Did you find and correct the condition? If yes, go to step 14 . If no, 

go to next step.  

12. Inspect the front stabilizer shaft and stabilizer shaft links for damage and repair as necessary. Did you 

find and correct the condition? If yes, go to step 14 . If no, go to next step.  

13. Inspect for control arm damage and repair as necessary. Did you find and correct the condition? If yes, go 

to next step.  

14. Operate the system in order to verify the repair. Did you correct the condition? If yes, system is okay. If 

no, go to step 3 .  

NOISE DIAGNOSIS - REAR SUSPENSION 

DEFINITION: Any noise emitted from the rear of the vehicle that is induced by VEHICLE SPEED or 
DRIVING TERRAIN as related to the rear suspension.  

1. Did you review the General Description and perform the necessary inspections? If yes, go to next step. If 

no, go to SYMPTOMS - SUSPENSION GENERAL DIAGNOSIS .  

2. Attempt to duplicate the condition. Road test the vehicle. Did you duplicate the condition? If yes, go to 

next step. If no, system is okay.  

3. Is the noise reactive to vehicle load or speed? If yes, go to next step. If no, go to step 6 .  

4. Inspect and adjust the tire Inflation. Inspect for unusual tire wear. Inspect the wheel nuts for looseness. 

Did you find and correct the condition? If yes, go to step 10 . If no, go to next step.  

5. Inspect the rear axle for rear axle noises. Did you find and correct the condition? If yes, go to step 10 . If 

no, go to next step.  

6. Bounce the rear of the vehicle in order to duplicate the noise. Did you duplicate the noise? If yes, go to 

next step. If no, go to step 9 .  

7. Raise the vehicle. Inspect the rear suspension components for looseness and tighten as necessary. Inspect 

the rear suspension components for damage and repair as necessary. Did you find and correct the 
condition? If yes, go to step 10 . If no, go to next step.  

8. Inspect the rear shock absorber. Did you complete the inspection? If yes, go to step 10 . If no, go to next 

step.  

9. Install the J-39570 Chassis Ear or equivalent. See SPECIAL TOOLS . Bounce the rear of the vehicle, 

using the J-39570 or equivalent, in order to locate the source of the noise. If necessary road test the 
vehicle. Repair or replace any defective component as necessary. Did you find and correct the condition? 
If yes, go to next step. If no, system is okay.  

10. Operate the system in order to verify the repair. Did you correct the condition? If yes, system is okay. If 

no, go to step 3 .  

POOR DIRECTIONAL STABILITY 

DEFINITION: Driver is unable to maintain consistent, predictable vehicle driving control in any direction.  

1. Did you review the General Description and perform the necessary inspections? If yes, go to next step. If 

no, go to SYMPTOMS - SUSPENSION GENERAL DIAGNOSIS . 

 

2004 Hummer H2 

2003-04 SUSPENSION General Diagnosis - H2

  

2. Verify that the directional stability is poor. Does the system operate normally? If yes, system is okay. If 

no, go to next step.  

3. Inspect the front stabilizer fasteners for looseness. Inspect for damaged stabilizer bar, stabilizer bushings, 

or damaged and missing stabilizer links. Did you find and correct the condition? If yes, go to step 10 . If 
no, go to next step.  

4. Inspect control arms, ball joints, and inner and outer tie rod ends for wear and damage. Did you find and 

correct the condition? If yes, go to step 10 . If no, go to next step.  

5. Inspect the wheel bearing. Did you find and correct the condition? If yes, go to step 10 . If no, go to next 

step.  

6. Inspect the vehicle trim height. Did you find and correct the condition? If yes, go to step 10 . If no, go to 

next step.  

7. Inspect the steering column for looseness. Did you find and correct the condition? If yes, go to step 10 . If 

no, go to next step.  

8. Inspect the steering gear mounting bolts for looseness. Did you find and correct the condition? If yes, go 

to step 10 . If no, go to next step.  

9. Inspect and adjust the wheel alignment as necessary. Did you complete the alignment? Go to next step.  

10. Operate the vehicle in order to verify the repair. Did you correct the condition? If yes, system is okay. If 

no, go to step 3 .  

RIDE DIAGNOSIS 

1. Did you review the General Description and perform the necessary inspections? If yes, go to next step. If 

no, go to SYMPTOMS - SUSPENSION GENERAL DIAGNOSIS .  

2.  

Verify that the ride is too soft or too hard. Does the vehicle ride normally? If yes, then system is okay. If 
no, go to next step.  

3. Inspect the tires for the proper inflation pressure. Is the tire inflation pressure correct? If yes, go to step 7 . 

If no, go to next step.  

4. Inspect the vehicle trim height. Refer to TRIM HEIGHT INSPECTION PROCEDURE . Did you find 

and correct the condition? If yes, go to step 7 . If no, go to next step.  

5. Inspect the strut and shock absorbers. Refer to STRUTS OR SHOCK ABSORBERS ON-VEHICLE 

TESTING . Inspect torsion bars and springs. Did you find and correct the condition? If yes, go to step 7 . 
If no, go to next step.  

6. If equipped with the Air Suspension system refer to Air Suspension. Did you find and correct a 

condition? If yes, go to next step. If no, system is okay.  

7. Drive the vehicle in order to verify the repair. Did you correct the condition? If yes, system is okay. If no, 

go to step 3 .  

STRUTS OR SHOCK ABSORBERS ON-VEHICLE TESTING 

1. Did you review the General Description and perform the necessary inspections? If yes, go to next step. If 

NOTE:

Verify the vehicle suspension package RPO. 

 

2004 Hummer H2 

2003-04 SUSPENSION General Diagnosis - H2

  

no, go to SYMPTOMS - SUSPENSION GENERAL DIAGNOSIS .  

2. Verify that the customer's concern is present. Does the vehicle operate normally? If yes, system is okay. 

If no, go to next step.  

3.  

Inspect each shock absorber for external fluid leakage. Is a strut or shock absorber leaking? If yes, go to 
step 5 . If no, go to next step.  

4. Use your hands in order to lift up and push down each corner of the vehicle 3 times. Remove your hands 

from the vehicle. Locate a shock or strut that exceeds 2 cycles. Did you locate shock or strut that exceeds 
2 cycles? If yes, go to next step. If no, go to step 6 .  

5.  

Replace the shock absorber. After replacing shock absorber, go to next step.  

6. Operate the vehicle in order to verify the repair. Did you correct the condition? If yes, system is okay. If 

no, go to step 3 .  

SUSPENSION BOTTOMS 

DEFINITION: A loud bang or thump that can usually be felt and/or heard when the vehicle is driven over 
bumps. This condition is commonly noticed when the vehicle trim height is too low.  

1. Did you review the General Description and perform the necessary inspections? If yes, go to next step. If 

no, go to SYMPTOMS - SUSPENSION GENERAL DIAGNOSIS .  

2. Verify that the suspension bottoms. Does the vehicle operate normally? If yes, system okay. If no, go to 

next step.  

3. Check for vehicle overloading and correct the overloading condition as necessary. Did you find and 

correct the condition? If yes, go to step 6 . If no, go to next step.  

4. Inspect the shock absorbers, coil springs, and torsion bars for damage or wear and repair as necessary. 

Did you find and correct the condition? If yes, go to step 6 . If no, go to next step.  

5. Inspect the vehicle trim height. Refer to TRIM HEIGHT INSPECTION PROCEDURE . Did you 

complete the trim height inspection procedure? If yes, go to next step.  

6. Operate the vehicle in order to verify the repair. Did you correct the condition? If yes, system is okay. If 

no, go to step 3 .  

TRIM HEIGHT INSPECTION PROCEDURE 

Trim Height Measurements 

Trim height is a predetermined measurement relating to vehicle ride height. Incorrect trim heights can cause 
bottoming out over bumps, damage to the suspension components and symptoms similar to wheel alignment 
problems. Check the trim heights when diagnosing suspension concerns and before checking the wheel 

NOTE:

A light film of oil on the top portion of the shock reservoir is normal. 

NOTE:

Inspect the vehicle trim height in order to correct any possible causes of 
shock/strut failures. Refer to TRIM HEIGHT INSPECTION PROCEDURE . 

 

2004 Hummer H2 

2003-04 SUSPENSION General Diagnosis - H2

  

alignment. Perform the following before measuring the trim heights:  

1. Set the tire pressures to the pressure shown on the certification label.  

2. Check the fuel level. Add additional weight if necessary to simulate a full tank.  

3. Make sure the rear compartment is empty except for the spare tire.  

4. Make sure the vehicle is on a level surface, such as an alignment rack.  

Z Height Measurement 

1. Lift the front bumper of the vehicle up about 38 mm (1.5 in).  

2. Remove your hands.  

3. Allow the vehicle to settle into position.  

4. Repeat this jouncing operation 2 more times for a total of 3 times.  

5. Measure from the pivot bolt center line (3) down to the lower corner (5) of the lower ball joint (1) in 

order to obtain the Z height measurement (4). See Fig. 4 . 

Fig. 4: Z Height Measurement 
Courtesy of GENERAL MOTORS CORP. 

6. Push the front bumper of the vehicle down about 38 mm (1.5 in).  

7. Remove your hands.  

8. Allow the vehicle to rise.  

9. Repeat the operation for a total of 3 times.  

10. Measure the Z dimension.  

11. Measure the Z dimension. The true Z height dimension number is the average of the high and the low 

 

2004 Hummer H2 

2003-04 SUSPENSION General Diagnosis - H2