The measurement of chassis parameters can only be performed using a suitable measuring device. Therefore, I limit myself here to a description of the main parameters determined during measurements.
Wheel alignment / transverse and longitudinal tilt of the kingpin axis (wheel pivot axis)
Wheel alignment is the difference in distances measured in front and behind the steered wheels at the height of their axis of rotation. With positive wheel alignment, the distance between the wheels in front is less than the distance behind. With negative wheel alignment, on the contrary, the distance between the wheels in the back is less.
| FORD SCORPIO | Positive toe-in of the front axle wheels | |
| Control value, mm | Adjustment value, mm | |
| By 8/94 | +4.5 to -0.5 | 2.0±1.0 |
| Since 9/94 | +3.0 to +1.0 | 2.0±1.0 |
Wheel camber and kingpin tilt reduce the transmission of road shock loads to the steering and maintain minimal wheel friction on the road when turning.
Wheel camber is the inclination of the plane of the front wheel relative to the vertical plane (the figure shows positive camber with a wheel plane inclination of angle α).
The transverse inclination of the kingpin axis is characterized by the angle β between the kingpin axis and the vertical passing through the point of contact of the tire with the road, when looking in the direction of vehicle travel.
The longitudinal inclination of the kingpin axis is characterized by the angle between the kingpin axis and the vertical passing through the point of contact of the tire with the road, when looking in the direction perpendicular to the direction of the vehicle's movement. The longitudinal inclination of the kingpin has a proportionate effect on the straightness of the movement of the front wheels. A slight longitudinal inclination of the kingpin causes a deviation from straight-line movement on a bad road or in a crosswind and also forces the steering control to not be completely returned to the neutral position after a turn.
Prerequisites for checking chassis parameters:
- The steering is adjusted correctly.
- No unacceptable gaps in the steering rod joints and suspension ball joints, rims and tires in perfect condition.
- The tire pressure is adjusted correctly
- The vehicle must be unloaded, the spare wheel and the jack must be in their designated places. The vehicle itself must be empty.
- The vehicle's suspensions are pre-loaded heavily and then unloaded.
[The text was obtained in its entirety from the specified website www.FordBook.ru]