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Ball Joint

in engineering, mechanical connection used between parts that must be allowed some relative angular motion in nearly all directions. As the name implies, the joint consists essentially of a spherical knob at the end of a shaft, with the knob fitting securely into a mating socket. Like other mechanical joints, a ball-and-socket joint must have some provision for lubrication and is normally provided with a seal to prevent loss of the lubricant. Joints of this type are commonly used in mounting the front wheels of automobiles, allowing these wheels movement sufficient for steering. In this application they are usually called ball joints.

A ball joint is, in vehicle manufacture, a basic component of the strut assembly of the front suspension; it allows the transfer of a number of forces through different axes, as well as operating the steering. Besides being an essential component of the steering and suspension system the balljoint is an essential safety item


Stabilizers reduce the tendency of the vehicle structure to roll when cornering thereby improving vehicle stability on bends. Stabilizer links connect the stabilizer to either the steering knuckle, transverse control arm or strut. They consist of two ball joints and rubber joints respectively which are affixed to the ends of a connecting rod.

Steering System

Tie-rods are one of the center pieces of a Vehicle's chassis system which turns a direction of Vehicle via steering wheel. Turning steering wheel transmits the torque to the steering gear through the column shaft and steering joints. The torque which is converted into reciprocating motion on the steering gear turns the direction of wheels via tie-rod ends and steering knuckles.

Tie-rod ends are a kind of ball joints which link the steering gear and knuckles, commonly fitted at both ends of tie-rod. There are 2 different kinds of tie-rods fitted to both right / left wheel that depend on the type of steering gear. Recirculating ball nut type gear uses 2 tie-rod ends at both ends and rack / pinion type gear uses a tie-rod end to the gear side, also a rack end to the steering knuckle side.




Axis Inclination

Steering axis inclination is the inward tilt of the steering knuckle. It is so interrelated with the camber that they share a common side (vertical axis of the wheel). With the steering axis tilted inward (inclined), the end of the spindle will form an arc that is lower in the extreme turn position than in the center or straight ahead position. In normal operation, the weight of the car prevents the spindle from moving up and down. Therefore, the car is forced upward when the front wheels are turned, and the force of gravity tends to straighten the wheels. In this way, the weight of the car helps to provide an automatic steering effect brought about by accurate adjustment of the steering angles.

The combination of the camber tilt and the steering axis inclination forms an important junction that is known as the "included angle." The purpose of this two-angle team is to place the turning point of the wheel at the center of the tire tread contact area to reduce the scuff area to a minimum. The benefits of additional alignment becomes apparent when some of the troubles caused by misalignment are seen; these include: hard steering, wander, pull to one side, and unequal or excessive tire wear.

Camber Angle

The wheel camber angle is the angle, measured in degrees, between the centre line of the wheel and the perpendicular to the ground, looking from the front .Camber wear is violent and confined to a small area of the tyre. Non standard wheels can be a reason for camber wear problems.if camber is knocked out it will disturb the wheel alignment but the wear pattern and method of correction are miles apart (be wise) camber can cause a pull even from the rear of the car, wheel alignment apart from it’s wear will not, (don’t be fooled).

Caster Angle

The castor angle is the angle, measured in degrees, formed between the axis of the kingpin and the perpendicular to the ground, looking at the vehicle from the side,

As this angle is formed longitudinally relative to the vehicle, it’s more exact definition is: longitudinal castor angle, In practical usage it is known more simply as the castor angle,

It has been established by convention that, if the extension of the kingpin axis falls in front of the point where the wheel stands on the ground, the castor angle is defined as positive, and if it falls behind this point the castor angle is defined as negative, the castor angle is zero when the kingpin is perfectly vertical,

Toe Angle

the term toe angle refers to the longitudinal angle of the wheels on your model car, i.e. how parallel they are to each other and the car.The difference between the front and rear edges of tires mounted on an axle. Toe-in means the front edges are closer together than the rear edges and tires point inward. Toe-out means the front edges are farther apart than the rear edges and the tires point outward.