GM Service Manual Online
For 1990-2009 cars only

Step

Action

Yes

No

DEFINITION: Lead/pull is the deviation of the vehicle from a straight path on a level road with no pressure on the steering wheel. Use the lead/pull correction table in order to verify that improper wheel alignment or worn components are not mistaken for tire lead.

1

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

Go to Step 2

Go to Symptoms - Suspension General Diagnosis

2

Road test the vehicle in order to verify the complaint. Select a smooth level surface to perform the test.

Does the vehicle operate normally?

System OK

Go to Step 3

3

Inspect the tire/wheel assemblies for the following conditions:

    • Inspect for correct tire pressure and adjust as necessary.
         Refer to Tire Inflation Pressure Specifications in Maintenance and Lubrication.
    • Inspect for correct tire size and repair as necessary.
        Refer to Vehicle Certification Label in General Information.
    • Check for abnormal tire ware.

Did you find and correct the condition?

Go to Step 11

Go to Step 4

4

Perform the Radial Tire Lead/Pull Correction in Tires and Wheels.

Did you find and correct the condition?

Go to Step 11

Go to Step 5

5

Inspect the front/rear suspensions for the following conditions:

    • Vehicle trim height
        . Refer to Trim Height Inspection .
    • Excessive wear or loose components.
        Refer to Symptoms - Suspension General Diagnosis , Symptoms - Power Steering System or Steering Linkage Inspection in Steering Linkage (Non-Rack and Pinion).
    • Excessive wheel bearing play
        . Refer to Wheel Bearings Diagnosis .

Do any of the above conditions apply?

Go to Step 10

Go to Step 6

6

Inspect the brake system for brake drag. Refer to Diagnostic Starting Point - Hydraulic Brakes in Hydraulic Brakes.

Did you find and correct the condition?

Go to Step 11

Go to Step 7

7

Inspect the steering gear valve for an unbalance.

If this is the cause, steering effort will be very light in the direction of the lead and effort will be heavy in the opposite direction with the vehicle parked on a smooth level surface.

Does the above condition apply?

Go to Step 9

Go to Step 8

8

Inspect the wheel alignment and adjust as necessary. Refer to Wheel Alignment Measurement in Wheel Alignment.

Did you correct the condition?

Go to Step 11

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9

Replace the steering gear valve. Refer to Steering Gear Replacement in Power Steering System.

Did you complete the repair?

Go to Step 11

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10

Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

Repair/replace components as necessary.

    • Tighten components to specifications. Refer to Fastener Tightening Specifications in Front Suspension or Fastener Tightening Specifications in Rear Suspension.
    • Replace the wheel bearings. Refer to Front Wheel Hub, Bearing, and Seal Replacement in Front Suspension.

Did you complete the repair?

Go to Step 11

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11

Operate the vehicle in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 3