Opel Corsa B 1993–2000 Service and Repair Manual: Wheel alignment and steering angles - general information

Accurate front wheel alignment is essential for precise steering and handling, and for even tyre wear. Before carrying out any checking or adjusting operations, make sure that the tyres are correctly inflated, that all steering and suspension joints and linkages are in sound condition and that the wheels are not buckled or distorted, particularly around the rims. It will also be necessary to have the car positioned on flat level ground with enough space to push the car backwards and forwards through about half its length.

Front wheel alignment consists of four factors: Camber is the angle at which the roadwheels are set from the vertical when viewed from the front or rear of the vehicle.

Positive camber is the angle (in degrees) that the wheels are tilted outwards at the top from the vertical.

Castor is the angle between the steering axis and a vertical line when viewed from each side of the vehicle. Positive castor is indicated when the steering axis is inclined towards the rear of the vehicle at its upper end.

Steering axis inclination is the angle, when viewed from the front or rear of the vehicle, between the vertical and an imaginary line drawn between the upper and lower front suspension strut mountings.

Toe setting is the amount by which the distance between the front inside edges of the roadwheel differs from that between the rear inside edges, when measured at hub height. If the distance between the front edges is less than that at the rear, the wheels are said to toe-in. If it is greater than at the rear, the wheels toe-out.

Camber, castor and steering axis inclination are set during manufacture and are not adjustable. Unless the vehicle has suffered accident damage, or there is gross wear in the suspension mountings or joints, it can be assumed that these settings are correct. If for any reason it is believed that they are not correct, the task of checking them should be left to a GM dealer who will have the necessary special equipment needed to measure the small angles involved.

It is, however, within the scope of the home mechanic to check and adjust the front wheel toe setting. To do this a tracking gauge must first be obtained. Two types of gauges are available and can be obtained from motor accessory shops. The first type measures the distance between the front and rear inside edges of the roadwheels, as previously described, with the car stationary. The second type, known as a scuff plate, measures the actual position of the contact surface of the tyre, in relation to the road surface, with the vehicle in motion. This is done by pushing or driving the front tyre over a plate which then moves slightly according to the scuff of the tyre and shows this movement on a scale.

Both types have their advantages and disadvantages, but either can give satisfactory results if used correctly and carefully.

Many tyre specialists will also check toe settings free or for a nominal charge.

Make sure that the steering is in the straight-ahead position when making measurements.

If adjustment is found to be necessary, clean the ends of the tie-rods in the area of the adjustment pin and clamp bolts.

Slacken the clamp bolts (one on each tie-rod balljoint and one on each tie-rod) and turn the adjustment pin on each tie-rod by the same amount in the same direction (see illustration). Only turn each pin by a quarter turn at a time before rechecking.

Toe adjustment points (only one side shown)

1. Clamp bolts
2. Adjustment pin

When adjustment is correct, tighten the clamp bolts to the specified torque. Check that the tie-rod lengths are equal to within 5 mm and that the steering wheel spokes are in the correct straight-ahead position.