Standing Start Acceleration (Launch Shudder) Test

The purpose of this test is to duplicate a vibration called launch shudder. In some cases, a powertrain mount or an exhaust ground-out may also be the cause of the vibration, depending on the symptoms.

CAUTION: Refer to Road Test Caution in Service Precautions.

1. With the vehicle at a complete stop and in gear, remove your foot from the brake pedal.
2. Accelerate to 48-64 km/h (30-40 mph) while looking for vibrations that match the customer's description.
Other possible causes of launch shudder include the following conditions:
- Incorrect trim height. Refer to Trim Height Specifications in Suspension General Diagnosis.
- A worn or damaged drive axle CV joint
- A ground-out through the engine or transmission mounts
- Faulty exhaust hangers and mounts