Measuring Wheel Alignment

Steering and vibration complaints are not always the result of improper alignment. In order to diagnose a condition in the power steering system, refer to DIAGNOSTIC STARTING POINT - POWER STEERING SYSTEM . In order to diagnose a condition in the steering wheel and column, refer to DIAGNOSTIC STARTING POINT - STEERING COLUMN . In order to diagnose a condition in the suspension, refer to DIAGNOSTIC STARTING POINT - SUSPENSION GENERAL DIAGNOSIS . In order to diagnose a vibration, refer to DIAGNOSTIC STARTING POINT - VIBRATION DIAGNOSIS AND CORRECTION .

Before making any adjustment affecting wheel alignment, perform the following inspections and adjustments in order to ensure correct alignment readings:

• Inspect the tires for the following conditions:
  • Pressure
  • Wear
  • Size
  • Brand
  • Construction
  • Balance
  • Runout
• Inspect the runout of the wheels. Refer to TIRE AND WHEEL RUNOUT SPECIFICATIONS .
• Inspect the wheel bearings for runout. Refer to HUB/AXLE FLANGE AND WHEEL STUD RUNOUT INSPECTION .
• Inspect the wheel bearings for looseness. Refer to WHEEL BEARINGS DIAGNOSIS in Suspension General Diagnosis.
• Inspect the following components for looseness or wear:
  • The front knuckles
  • The control arm ball studs
  • The control arm bushings
  • The outer tie rods
  • The inner tie rods
  • The steering gear
  • The stabilizer shafts
  • The front struts
  • The rear coil springs
  • The rear shock absorbers
• Inspect the struts and the shock absorbers for leaks.
• Inspect the vehicle trim height. Refer to TRIM HEIGHT INSPECTION PROCEDURE in Suspension General Diagnosis.
• Inspect the remaining suspension and steering components for damage. Replace all damaged parts prior to adjusting wheel alignment.
• Inspect the fuel level. The fuel tank should be full or the vehicle should have compensating ballast.

Give consideration to excess loads, such as tool boxes, sample cases, etc. If these items are normally in the vehicle, these items should remain in the vehicle during the alignment adjustments. Give consideration to the condition of the equipment being used for the alignment. Follow the equipment manufacturer's instructions.

Satisfactory vehicle operation may occur over a wide range of alignment settings. However, if the setting exceeds the service allowable specifications, correct the alignment to the service preferred specifications. Refer to WHEEL ALIGNMENT SPECIFICATIONS (FWD)  or WHEEL ALIGNMENT SPECIFICATIONS (AWD)  .

Perform the following steps to measure the front alignment angles:

1. Install the alignment equipment according to the manufacturer's instructions.
2. Perform the following procedure to normalize the suspension prior to measuring the angles:
   1. 2.1 Bounce the front bumper lightly 3 times.
   2. 2.2 Bounce the rear bumper lightly 3 times.
3. Measure the alignment angles.
4. Record the readings.
5. If the vehicle has 4WD, adjust the rear camber and the rear toe. Refer to REAR CAMBER AND TOE ADJUSTMENT (AWD)  .
6. Adjust the front camber. Refer to FRONT CAMBER ADJUSTMENT  .
7. Adjust the front toe. Refer to FRONT TOE ADJUSTMENT  .