Automotive Terms Dictionary

A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

B-Pillar
The roof support between a vehicle's front door window and rear side window, if there is one.

Balance Shaft
A shaft designed so that, as it turns, it counter rotates the rotational direction of the engine crankshaft in a manner that reduces or cancels out some of the vibration produced by the engine.

Ball Joint
A flexible joint consisting of a ball within a socket. Ball joints act as pivots which allow turning of the front wheels and compensate for changes in the wheel and steering geometries that occur while driving.

Base-Coat/Clear Coat
Final/extra coat of paint layer over final color coats which provides a deep and wet look shine to resist fading.

Belted Radial Tires
A reinforcing bank, normally textile, fiberglass or steel to strengthen the tread area of a tire.

Bias-Ply Tires
A type of tire in which the plies or layers of cord in the tire casing are laid diagonally, criss-crossing one another at an angle of 30 to 40 degrees.

Body-On-Frame Construction
Body structure and frame are two separate parts but are attached.

Body shop
service outlet specializing in vehicle body repair work.

Bore
The diameter of an engine cylinder or bearing.

Brake Fade
When repeated braking, results in build-up of heat which causes reduction or "fading" of braking power and breaking is less effective.

Brake Horsepower (BHP)
The actual horsepower of an engine, measured by a brake attached to the driving shaft and recorded by a dynamometer.

Brake Master Cylinder
Crucial part of your braking system, activated by applying pressure on the brake pedal. The piston produces hydraulic pressure that pushes fluid through the lines and wheel cylinders. This forces the brake lining or pad against the drum or disc to slow the movement of the car.

Brake Pads
In a disc system, they are the replaceable flat segments consisting of a rigid backing plate plus frictional lining that takes the place of the shoe and lining in a drum brake. Brake pads are sometimes referred to as brake pucks.

Brake Shoe
The arc-shaped carrier to which the brake linings are mounted in a drum brake. They also force the lining against the rotating drum during braking.

Brakes, Disc
A type of braking system in which brake shoes, in a vise-like caliper, grip a revolving disk ounted on a wheel to slow or stop disc and wheel rotation for braking.

Brakes, Drum
A type of braking system that utilizes a metal drum mounted on a wheel to form the outer shell of a brake. The brake shoes press against the drum to slow or stop drum and wheel rotation for braking.