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Bed Rail

The flat surface on top of each side of a pickup truck's bed. Also called side rails.

Bed Stiffener

A product designed to stiffen a pickup's bed to reduce flex when the tailgate is removed.

Bed Tray

A cross between a bed mat and a drop-in bedliner that covers the floor of a pickup's bed, just like a mat, but that features slightly raised sides to contain spills or loose cargo. Bed trays are made from polyethylene, like drop-in bedliners, so they also are resistant to chemicals and UV rays. They are like the cargo trays that are available for the cargo area of vans and SUVs

Bed-mount Bike Rack

A bike rack designed to go in the bed of a pickup truck. Some of the fork-mount bike rack designs feature a bar that extends across the width of the bed, to which you attach the front forks. Another type of bed-mount bike rack uses a clamping system to attach a bike (with or without the front wheel in place) to the pickup's bed rail. Some of the latter designs can secure two or more bikes in series (with one attached to the bed rail, and a second bike attached to the first).

Beef

A term used for beef up.

Beef Up

To strengthen and/or reinforce.

Beehive Spring

A spring that is wound in the shape of a beehive.

Beepig Backup Light Bulb

A replacement bulb for a reverse light in a vehicle that not only illuminates when the vehicle is shifted into reverse, but also beeps to alert other motorists and pedestrians.

Before Bottom Dead Center

The position of a piston approaching the bottom of its intake or combustion stroke.

Before Top Center (BTC)

A piston as it is approaching the top of its stroke.

Before Top Dead Center (BTPC)

Any position of the piston between bottom dead center and top dead center on its upward stroke.

Bell Housing

1.A bell-shaped housing attached between the engine and the transmission used to house the torque converter or clutch assembly 2. A term often used for clutch housing.

Bell-mouthed Drum

A well-worn brake drum that is deformed so that its open end has a larger diameter than its closed end.

Bellcrank

A part that pivots to transfer motion at a right angle (90 degrees).

Belleville Spring

A diaphragm type spring used to help apply and release a multiple-disc clutch.

Belleville Washer

A circular disk formed into a conical shape. When a load is applied, the disk tends to flatten, constituting a spring action. May be referred to as a coned-disk spring.

Bellows

A flexible chamber that can be expanded to draw a fluid or vapor in and compressed to pressurize the fluid or vapor.

Belly Pan

Body panel(s) covering the bottom of a competition vehicle to reduce the coefficient of drag.

Belly Tank

A tear shaped, World War II aircraft auxiliary fuel tank used as the body for a lakester.

Belt

1. In a tire, the belt(s), generally steel, restrict ply movement and provide tread stability and resistance to deformation, providing longer tread wear and reducing heat buildup in the tire. 2. A device used to drive the water pump and/or other auxiliary devices, such as the alternator, off the engine.