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

Road test the vehicle to verify the concern.

Select a smooth level surface to perform the test.

Does the condition exist?

Go to Step 2

System OK

2

Inspect the tire/wheel assemblies for the following:

    • Correct tire pressure. Refer to Tire Inflation Pressure Specifications in Maintenance and Lubrication.
    • Correct tire size. Refer to Vehicle Certification Label in General Information.

Do any of the above conditions apply?

Go to Step 3

Go to Step 4

3

Repair/replace the tire/wheel assemblies as necessary.

Is the repair complete?

Go to Step 14

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4

Inspect the front/rear suspensions for the following:

    •  Vehicle trim height. Refer to Trim Height Inspection .
    • Excessive wear or loose components. Refer to Suspension General Diagnosis .
    • Excessive wheel bearing play. Refer to Wheel Bearings Diagnosis - Tapered .

Do any of the above conditions apply?

Go to Step 5

Go to Step 6

5

Repair/replace components as necessary.

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

Is the repair complete?

Go to Step 14

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6

Inspect the Brake system for Brake drag. Refer to Brakes Drag in Hydraulic Brakes.

Do any of the above conditions apply?

Go to Step 7

Go to Step 8

7

Repair/replace components as necessary.

Is the repair complete?

Go to Step 14

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8

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 10

9

Replace the steering gear valve. Refer to Steering Gear Valve Replacement - Off Vehicle .

Is the repair complete?

Go to Step 14

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10

Inspect the wheel alignment. Refer to Wheel Alignment Measurement in Wheel Alignment.

Is the wheel alignment in specifications?

Go to Step 12

Go to Step 11

11

Adjust alignment to specifications. Refer to Wheel Alignment Measurement in Wheel Alignment.

Is the repair complete?

Go to Step 14

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12

  1. Cross-switch the front tire/wheel assemblies.
  2. Road test the vehicle on a smooth level surface.

Does the vehicle still lead/pull?

Go to Step 11

System OK

13

Does the vehicle lead/pull in the opposite direction?

Go to Radial Tire Lead/Pull Correction in Tires and Wheels

Go to Step 14

14

Verify proper system operation.

Does the original condition still exist?

Go to Step 1

System Ok