BigSloth
Senior Member
- Joined
- Jun 27, 2013
- Posts
- 721
- Reaction score
- 189
- Location
- Mobile, AL
- Ram Year
- 2014 1500 CCSB Black Express
- Engine
- 5.7 Hemi
What is the Caster Angle?
Late to the party, but here you go.
Caster is the measured difference in angle between the steering axis tilt, and vertical. Think of it as the angle between this | and this /. Your steering axis is an imaginary line drawn through the pivot points of your front suspension, in our case, the ball joints. If you were to draw a line through the center of the lower ball joint, and continue it through the center of the upper ball joint, that would be your steering axis. The difference in angle between that line and a vertical line drawn upwards from the center of the wheel is your caster angle, and is measured in degrees.
It's called caster because it's what allows your wheels to return to the straight ahead position after a turn, and for them to remain that way unless you steer otherwise, like a caster on a shopping cart. Vehicles that have less caster have less responsive steering that is not going to return the steering wheel to center very quickly. Vehicles with a high caster angle have more responsive, quick returning steering.
Since caster is measured as the difference between the steering axis and vertical, if you do anything to alter the stance or ride height of either end of the truck, you will affect the caster angle. If you could see the imaginary lines when looking from the drivers side of the truck, the angle would look like this |/. Dropping the rear of the truck tilts it further back, increasing caster. Raising the front does the same.