This document discusses steering geometry and components. It describes camber as the tilt of car wheels from vertical, with positive camber meaning the top tilts outward. It also discusses king pin inclination of 7-8 degrees, combined angle of 9-10 degrees, and scrub radius of up to 12mm. The steering linkage transmits movement from the steering gear to the front wheels, using components like the pitman arm, center link, idler arm, tie rod, and ball sockets between components. Proper adjustment and lubrication of the linkage joints is important.

1. Steering geometry
Toe out
(TOP RIGHT) Positive camber: The bottoms of
the wheels are closer together than the tops.
(TOP LEFT) Negative camber: The tops of the
wheels are closer together than the bottoms.

2. Steering geometry
Slip angle

3. camber angle

4. Camber
Camber is the tilt of the car wheels from the vertical.
Camber is positive if the tilt is outward at the top.
Camber is also called “wheel rake”.
Camber should not generally exceed 2°. However the
exact amount of camber is specified taking into
account the king pin inclination.
King Pin Inclination (Steering axis Inclination)
Inclination of the king pin from vertical is called
the king pin inclination or king pin rake.
Effect :-King pin inclination helpsthe straight
ahead recovery, thus provides stability.
Amount : About 7 to 8 degrees

5. Combined angle
Combined angle or included angle is the angle formed
in the vertical plane between the wheel centre line and
the king pin centre line ( or steering axis).
Combine angle is equal to camber plus king pin
inclination.
Combined angle may be 9-10 degrees. And the scrub
radius should be upto about 12mm
Scrub radius
The forward tractive force acts at the point on the road
where the steering axis or the king pin axis meet when
projected. The road resistance acts at the wheel
contact point on the road. The distance between these
two points is called scrub radius.

6. caster angle

9. STEERING GEAR BOXES

12. RECIRCULATING BALL SCREW

15. STEERING LINKAGES
A steering linkage is a combination of rods and arms that transmit movement of
the steering gear to the front wheels, while allowing for wheel movement while
the vehicle is in motion.

17. The pitman arm transfers steering mechanism motion to the steering linkag
The pitmanarm is splined to the steering mechanisms output shaft(pitman arm
shaft). A large nut and lock washer securethe pitman arm to the output shaft. The
outer end of the pitman arm normally uses a ball-and-socket joint connect to
the center link.
Centre link is simply a steel bar thatconnects the steering arms (pitman arm, tie-
rod ends,and idler arm) together. The turning action of the steering
mechanism is transmitted to the center link through the pitman arm
The center link is hinged on the opposite end of the pitman arm by means of an
idler arm. Theidler arm supports the free end of the center link andallows it to
move left and right with ease. The idler armbolts to the frame or subframe
Ball sockets are like small ball joints;they provide for motion in all directions
between twoconnected components. Ball sockets are needed so
thesteering linkage is NOT damaged or bent when thewheels turn or move up
and down over rough
roads.Ball sockets are filled with grease to reduce frictionand wear. Some h
ave a grease fitting that allowschassis grease to be inserted with a grease
gun. Othersare sealed by the manufacturer and cannot be serviced

18. STEERING GEOMETRY

25. The arms and rods of the steering linkage have ballends or ball-and-
socket ends to provide a swivelconnection between them. These joined ends haveg
rease fittings, dust seals or boots, and many of themhave end-play adjustment devices.
These joints anddevices must be adjusted and lubricated regularly
The arms, rods, and joints of steering linkage in yourequipment may be arranged
differently from thoseshown in figure, but you will find them in the samegeneral
location in the front and underneath the vehicle.
The tie rod is usually behind the axle and keeps thefront wheels in proper alignment.
The tie rod is dividedinto two lengths and is connected to the steering gearnear the
center of the vehicle to provide for easiersteering and maximum leverage.
The drag link between the steering arm and thepitman arm may be long or short,
depending on theinstallation
The pitman arm is splined to the shaft extendingfrom the steering gear case. It moves
in an arc with itsposition, depending on which direction the steeringwheel is turned.
The arm is vertical when the frontwheels are straight ahead. Therefore, the length of
thedrag link is determined by the distance between thesteering arm and the vertical
position of the pitman arm.Unlike the tie rods, the length of the drag link is fixed.