Vibration Conditions

The types of vibrations that can be felt in the vehicle may be divided into three groups:
- Vibrations of rotating parts of the vehicle.
- Body and frame vibrations caused by powertrain, wind or road conditions.
- Moans or resonance vibrations from a stressed engine, exhaust system, suspension or driveline.

These vehicle vibrations can also be separated into those that occur at low speed and those that occur at higher speed. Since the line between low and high speed vibrations is not always clear, some vibrations will overlap the two ranges.

Typical Low-Speed Vibrations (Less Than 72 km/h [45 mph]):
- Exhaust vibration.
- Engine harshness.
- Driveline vibration.
- Power steering pump vibrations.
- Air conditioner compressor or drive belt vibrations.
- Brake roughness or harshness.
- Driveline roughness.
- Clutch shudder.

Typical High-Speed Vibrations (Above 72 km/h [45 mph]):
- Driveshaft imbalance.
- Excessive tire-wheel and drum assembly imbalance.
- Tire roughness.
- Excessive tire and wheel runout.
- Worn suspension components.
- Front end accessory vibrations.
- Exhaust vibration.

A hard ride or harshness is usually caused by the tires or suspension system. The following is a list of possible concerns:
- Overinflated, wrong size or wrong type tire installed on the vehicle.
- Suspension insufficiently lubricated.
- Worn suspension components.
- Suspension components installed with preload on pivot point, bearings and bushings.
- Bent or bound-up shock absorbers.

Other conditions that effect ride quality may be summarized as follows:
- Vehicle bounce or sway.
- Vehicle pitch.
- Vehicle roll.