Alignment: Description and Operation

Super Duty Series vehicle caster and camber correction requirements arc factory-determined. Adjusters are available to correct a caster/camber measurement that does not meet specification. Before changing the production caster/camber adjuster, thoroughly inspect the suspension system to locate worn or damaged components that may have caused the setting to change.

Negative And Positive Camber

Negative and Positive Camber:

Camber is the vertical tilt of the wheel when viewed from the front. Camber can be positive or negative and has a direct effect on tire wear.

Caster And Frame Angle

Caster And Frame Angle:

Caster is the deviation from vertical of an imaginary line drawn through the ball joints when viewed from the side. The caster specifications in this section will give the vehicle the best directional stability characteristics when loaded and driven. The caster setting is not related to tire wear.

Dogtracking

Dogtracking:

Dogtracking is the condition in which the rear axle is not square to the chassis. Heavily crowned roads can give the illusion of dogtracking.

Drift/Pull
Pull is a tugging sensation, felt by the hands on the steering wheel, that must he overcome to keep the vehicle going straight.

Drift describes what a vehicle with this condition does with hands off the steering wheel.
^ A vehicle-related drift/pull, on a flat road, will cause a consistent deviation from the straight-ahead path and require constant steering input in the opposite direction to counteract the effect.
^ Drift/pull may be induced by conditions external to the vehicle (i.e., wind, road camber).

Poor Groove Feel
Poor groove feel is characterized by little or no buildup of turning effort felt in the steering wheel as the wheel is rocked slowly left and right within very small turns around center or straight-ahead (under 20 degrees of steering wheel turn). Efforts may be said to be "flat on center. "
^ Under 20 degrees of turn, most of the turning effort that builds up comes from the mesh of gear teeth in the steering gear. In this range, the steering wheel is not yet turned enough to feel the effort from the self-aligning forces at the road wheel or tire patch.
^ In the diagnosis of a readability problem, it is important to understand the difference between wander and poor groove feel.

Nibble
Sometimes confused with shimmy, nibble is a condition resulting from tire interaction with various road surfaces and observed by the driver as small rotational oscillations of the steering wheel.


Poor Returnability/Sticky Steering
Poor returnability and sticky steering is used to described the poor return of the wheel to center after a turn or the steering correction is completed.

Front Ride Height Measurement - F-250 and F-350, 4x2:

Front Ride Height Measurement - F-250 And F-350 (4X2)

Front Ride Height Measurement - F-250 and F-350, 4x4, and F-450, F-550:

Front Ride Height Measurement - F-250 and F-350, 4x4, and F-450, F-550

Rear Ride Height Measurement - 4x2:

Rear Ride Height Measurement - 4X2

Rear Ride Height Measurement - 4x4:

Rear Ride Height Measurement - 4X4


Shimmy
Shimmy, as observed by the driver, is large, consistent, rotational oscillations of the steering wheel resulting from large, side-to-side (lateral) tire/wheel movements.
Shimmy is usually experienced near 64 km/in (40 mph), and can begin or be amplified when the tire contacts pot holes or irregularities in the road surface.

Toe

Positive Toe (Toe In):

Positive Toe (Toe In)

Negative Toe (Toe Out):

Negative Toe (Toe Out)

The vehicle toe setting:
^ affects tire wear and directional stability.
^ must be checked after adding aftermarket equipment, such as a snowplow or body.

Wander
Wander is the tendency of the vehicle to require frequent, random left and right steering wheel corrections to maintain a straight path down a level road.

Wheel Track:

Wheel Track