Second-Order Driveline Vibration Symptoms

Second-Order driveline vibration has the following signs and symptoms:
- The vibration is always related to vehicle speed.
- The vibration is usually torque-sensitive.
- The vibration is worse under a torque load.

Launch shudder is the most common complaint of a second-order driveline vibration.
Launch shudder occurs during acceleration from 0 - 40 Kph (0 - 25 mph). Launch shudder appears as a low frequency shake, wobble, or shudder. The driver may feel the vibrations in the seat or steering wheel at low speeds of 0 - 24 km/h (0 - 15 mph). The vibrations will increase in frequency as the vehicle speed increases. Launch shudder feels more like driveline roughness at higher speeds of 24 - 40 km/h (15 - 25 mph). At speeds greater than 40 km/h (25 mph) the vibration usually disappears.
Launch shudder vibration is equal to a second-order vibration of the driveline The EVA will not perceive frequency information due to the transitory nature of launch shudder.