Vauxhall Workshop Service and Repair Manuals

What is the purpose of chassis alignment?

The theoretical wheel position is the position of the wheels parallel to the direction of travel. However, with this wheel position it is extremely difficult to keep the vehicle safely on the road.

The wheel position is determined by:

• Drive type (front/rear wheel drive)
• Wheelbase
• Track
• Toe
• Camber
• Kingpin inclination
• Castor
• Offset radius
• Toe variation

The geometric position of the wheels ensures that the forces acting on the wheel when the vehicle is being driven are taken into account and hence a higher level of safety and good handling are achieved.

Modern chassis designs are characterised by the following properties:

• Neutral steering and handling
• Good straight-line stability (tracking stability)
• Neutral cornering behaviour, i.e. a low degree of understeer or oversteer due to the lateral stability of the wheels even with high cornering speeds
• Low steering effort and quick response from the steering
• No disturbing influences on the steering wheel, such as impacts or vibrations from high stresses, for example when braking or accelerating or due to uneven road surfaces
• no/little transfer of disruptive influences to the passenger compartment

The chassis alignment is used to check the geometric wheel position specified by Opel/Vauxhall in order to guarantee safety and good handling in many different types of driving conditions