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DOT

An acronym for Department of Transportation.

DOT 3, 4, And 5

U.S. Department of Transportation specification numbers for hydraulic brake fluids.

DOT 39

Trade jargon for a disposable refrigerant cylinder. Disposable cylinders should never be refilled or used as compressed air tanks.

Dot Matrix

A type of display or printer output in which each alphanumeric character is made up of an array of small dots.

Double A-arm

A suspension system using two A-arms or A-frames to connect the chassis to the wheel spindle.

Double Cardian Joint

A near-constant-velocity universal joint consisting of two Cardian joints connected by a coupling yoke.

Double Century

Two-hundred miles per hour.

Double Clutch

A driving technique to minimize gear clash when shifting gears with a manual transmission.

Double Filament Lamp

A lamp designed for more than one function; used in the stoplight, tail light and the turn-signal circuits combined.

Double Flare

A flare on the end of tubing, made by folding it over to form a double face.

Double Pivot Control Arm

A term used for control arm.

Double Pole Double Throw (DPDT)

A term used to identify a switch configuration having six terminals that connects one pair to either of the other two pairs of terminals.

Double Pole Single Throw (DPST)

A term used to identify a switch configuration having four terminals that connect or disconnect two pairs of terminals simultaneously.

Double Ton

Two-hundred miles per hour.

Double Wishbone

A term used for double A-arm.

Double Wrap

A flexible type of brake band designed with two segments that provide flexibility, which increases self-energizing action.

Double-A Frame

A term used for double-A arm.

Double-acting Shock Absorber

A shock that provides a dampening effect on both compression and rebound.

Double-groove Valve Stem

A valve stem having two keeper grooves.

Double-hump Heads

A term used for camel-hump heads.