Found this out and pretty interesting to read.

FORCE FEEDBACK AND STEERING WHEEL SETUP
Vibration and Feedback

The following settings can be found in the Vibration and Feedback screen, in the Options menu.

Vibration Strength
The amount of wheel vibration from crashes, rumble strips, and other environmental effects.

Wheel Strength
This adjusts the overall strength of the steering forces. The amount of steering force is set based on personal preference and driving style. Setting the value too high may cause oscillation and an unrealistic feel to the force feedback.

Wheel Weight
Wheel Weight refers to the steering wheel’s friction. A higher value will increase the apparent weight of the wheel, and more force will be required to turn the wheel, providing increased stability at higher speeds. A lower value will make the turning lighter and easier, but potentially more difficult to maintain a straight direction at higher speeds.

Advanced Wheel Settings

The following settings can be found under Advanced Wheel Settings in the Controls menu.

Dead Zone
This can apply to the steering or to the throttle and brake pedals. It creates a dead area in which input is ignored and so control will remain at the default (e.g. straight ahead in the case of steering). This can be useful if you are finding it difficult to keep the car in a straight line, but note that a higher Linearity value (see below) may give a more desirable effect than increasing the dead zone, so consider trying that before increasing the dead zone.

Saturation
This can apply to the steering or to the throttle and brake pedals. Saturation sets the point at which maximum steering/pedal input is achieved, affecting for example the amount you need to press the throttle before maximum acceleration is achieved. If steering seems unresponsive, reducing the saturation will mean the steering reaches its maximum lock sooner.

Linearity
This applies to steering only and adjusts the relative sensitivity of steering around the centre point and the extremities. Unlike the Deadzone setting it does not eliminate player input. Positive values mean that the steering is less sensitive in the centre region and more sensitive when cornering at high lock. Negative values mean the opposite, so steering is more sensitive around the centre and less so when cornering.