A condition in which a vehicle turns at a smaller angle than that of the steering wheel input because of rear tire slippage. When this occurs, the steering wheel must be turned at a greater angle to achieve the desired turn.

• Understeer will be affected by the amount of wheel turn lock-to-lock, as well as the vehicle’s weight and the speed of the vehicle when encountering turns
• Oversteer, which means the vehicle turns more than steering wheel input and indicated by front tire slippage, can make the vehicle hard to control. Because of this, engineers often design suspensions that tend toward understeer as a safety measure

A type of body construction that doesn’t require a separate frame to provide structural strength or support for the vehicle’s mechanical components. Also called "unitized."

Wheels designed to be fastened to one side of the vehicle, front and rear. The wheel patterns or logos are meant to point to the front of the vehicle. Unidirectional wheels are interchangeable on one side of the vehicle only and usually also function as an air induction point to cool disc brake rotors.

With unitized body construction, the front, rear and side rails are welded together with the floor pan, crossmembers and torque boxes to form a single unit. Unitized body construction is used on all Ford cars excluding Crown Victoria.

A joint that transmits rotary motion between two shafts that aren’t in a straight line.

Components such as tires, wheels and brakes are not supported by the suspension and are considered unsprung weight.

• Reducing unsprung weight improves ride and handling by allowing the tires to respond more rapidly to road irregularities
• An independent rear suspension reduces unsprung weight by attaching the differential to the chassis rather than solidly mounting it with the axis

Treatment applied to body panels that helps resist stone and gravel damage to the paint finish.