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For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 2006 🢒 TopKick C-Series (Conventional) C6/C7/C8 🢒 General Information 🢒 Vibration Diagnosis and Correction 🢒 Vibration Analysis - Driveline

Test Description

The numbers below refer to the step numbers in the diagnostic table.

  1. First-order driveline vibrations can be caused by excessive runout of the propeller shaft.

Step

Action

Yes

No

1

Has the Vibration Analysis - Road Testing table been completed?

Go to Step 2

Go to Vibration Analysis - Road Testing

2

Inspect the following components for wear or damage:

    • Inspect the propeller shafts for dents, damage, missing weights, and undercoating.
    • Inspect the U-joints for damage and missing components.
    • Inspect the center bearings for damaged rubber components, worn bearings, or a cracked bracket.

Are any of the components listed worn or damaged?

Go to Step 3

Go to Step 4

3

Replace the damaged or missing components. Refer to one of the following procedures in Propeller Shaft:

Did you complete the replacement?

Go to Step 14

--

4

Measure the runout at the front of the forward-most rear axle propeller shaft. Refer to Propeller Shaft Runout Measurement .

Does the runout measurement require that the propeller shafts be replaced?

Go to Step 6

Go to Step 5

5
  1. Replace the transmission mount. Refer to one of the following procedures:
    2. •  Transmission Mount Replacement in Manual Transmission - Medium Duty
    •  Transmission Mount Replacement in Automatic Transmission - Allison
  2. Attempt to duplicate the customer's concern

Is the vibration still present?

Go to Step 6

Go to Step 14

6

Measure the runout of the complete propeller shafts. Refer to Propeller Shaft Runout Measurement .

Does the runout measurement require that the propeller shaft(s) be replaced?

Go to Step 7

Go to Step 8

7
  1. Replace the propeller shaft. Refer to appropriate procedure in Propeller Shaft:
  2. Attempt to duplicate the customer's concern.

Was the vibration reduced or eliminated?

Go to Step 14

Go to Step 8

8

Inspect the following components for wear or damage:

    • Inspect the propeller shafts for dents, damage, missing weights, and undercoating.
    • Inspect the U-joints for damage and missing components.
    • Inspect the center bearings for damaged rubber components, worn bearings, or a cracked bracket.

Are any of the components listed worn or damaged?

Go to Step 9

Go to Step 10

9

Replace the damaged or missing components. Refer to one of the following procedures in Propeller Shaft:

Did you complete the replacement?

Go to Step 14

--

10
  1. Measure the vehicle trim height. Refer to Trim Height Inspection in Suspension General Diagnosis.
  2. Adjust the vehicle trim height, if necessary.

Did you find and correct a condition?

Go to Step 11

Go to Step 12

11

Attempt to duplicate the customer's concern.

Was the vibration reduced or eliminated?

Go to Step 14

Go to Step 12

12

Measure the propeller shaft angles. Refer to Driveline Working Angles Measurement .

Do the propeller shaft angles require adjustment?

Go to Step 13

Go to Vibration Diagnostic Aids

13

Adjust the propeller shaft angles. Refer to Driveline Working Angles Adjustment .

Did you complete the repair?

Go to Step 14

--

14
  1. Install or connect any components that were removed or disconnected during diagnosis.
  2. Perform the Vibration Analysis - Road Testing table. Refer to Vibration Analysis - Road Testing .

Is the vibration still present?

Go to Step 2

System OK