HDL Glossary of Terms

A

AFV – Alternative Fueled Vehicle. A vehicle that runs on something other than gas or diesel.

B

Berth – Sleeping compartment behind the cab.
Bill of Lading – Itemized list of goods contained in a shipment.
Bunk – Sleeping compartment behind the cab.

C

Cabover – Cab-Over-Engine (COE). A type of truck design with the cab over the engine.
Cargo Weight – The weight of the loads, gear and supplies on a vehicle.
Cartage Company – A company that provides local pickup and delivery.
CB – Citizens Band Radio. This is a two-way radio system used to communicate traffic conditions, help requests, and conversation.
CDL – Commercial Driver’s License. Allows people to drive a truck or bus that weighs more than 26,001 pounds and is used in support of a business.
Chassis Weight – The empty weight of a vehicle. Also curb weight and tare weight.
Class A Driver – This class of license permits you to drive a Class 8 tractor, which is better known as a big rig
Class B Driver – This type of commercial driver’s license permits you to transport freight greater than 26,000 pounds gross vehicle weight (GVR) and with a single axle trailer.
COFC – Container On Flat Car. Shipping containers on flat railroad cars.
Common Carrier – A company that will carry freight for any customer, as opposed to a private or dedicated carrier that only works for one customer.
Container – Shipping Container. One giant box, about 20 or 40 feet long that will fit in ships’ holds and can also be carried by rail or truck. Some containers are lighter and longer and are only used in rail and road transportation.
Container Chassis – A trailer designed to carry containers.
Contract Carrier – A company that carries freight for a small number of customers under contract.
COVID-19 – Coronavirus disease
CPM – Cents per Mile. The per-mile rate at which drivers are paid.

D

DOTDepartment Of Transportation
DOT medical card – Administered by a certified medical examiner only after a driver meets the DOT physical requirements
Doubles – A combination of a truck and two trailers.
Drayage – Carrying freight a short distance as part of a longer trip. For example, a tractor picking up freight from a rail yard and carrying it 50 miles to its final destination.

E

EDI – Electronic Document Interchange. An electronic system for sharing transportation-related documents like bills of lading.
E-Log – A computerized system to keep track of their hours of service and miles. The carrier and dispatcher have instant access to this information, which improves their ability to schedule drivers appropriately. The federal government favors the use of E-Logs over traditional hand-written logs.
EOBR – Electric On-Board Recorder. A device that records information about a truck’s trip.

F

Fifth Wheel – The way tractors and trailers are connected. The fifth wheel accepts a trailer’s kingpin and supports the front end the trailer.
Flatbed – An open trailer used for carrying construction materials and equipment and other objects of unusual size and shape.
FMCSA – Federal Motor Carrier Safety Administration. Regulates the US commercial trucking industry.
Forced Dispatch – When the company dispatcher assigns a load, customer and delivery time to a driver and the driver must take the load or suffer consequences (such as being forced to wait around several hours or another day for another load, or even being fired).

G

GAWR – Gross Axle Weight Rating. The manufacturer’s rating of how much weight an axle can carry.
GCW – Gross Combination Weight. The total weight of an entire loaded vehicle including truck, trailer and cargo.
Governor – A device that regulates the truck’s top speed. Large fleets use these to ensure their drivers stay within guidelines to improve fuel efficiency and safety.
Grade – The steepness of a hill. A 5% grade means a hill rises 5 feet per 100.
GVW – Gross Vehicle Weight. The total weight of a vehicle and everything on it.
GVWR – Gross Vehicle Weight Rating. How much the manufacturer approves the vehicle to carry.

H

Hazmat – Hazardous materials.
Headache Rack – A barrier behind the truck cab designed to protect the driver from behind in the case of a load shifting forward from the trailer.
Hours-Of-Service – FMCSA safety regulations governing how long and when drivers may be on duty and driving.

J

Jackknife – When the tractor and trailer are at a sharp angle to one another.
JIT – Just-In-Time. The art of getting goods to a customer extremely close to the time he needs to sell it. This keeps the seller’s costs low by reducing inventory.

K

Kingpin (axle) – An axle’s wheels pivot around a kingpin.
Kingpin (trailer) – Connects the truck to trailer.

L

Landing Gear – Supports to hold up the front end of a trailer when it is not attached to a tractor.
LCV – Long Combination Vehicle. A vehicle longer than a double trailer, like a triple.
Lift Axle – An extra axle that can be lowered and put into use for a heavier load so that the vehicle can meet federal and local weight standards.
Logbook – A truck driver’s book for recording hours and activities during a 24-hour period.
Logistics – The art and science of getting people and materials where they need to be when they need to be there.
Long-haul – Driving long distances.
Lowboy – A flatbed trailer with a low deck used for carrying taller materials like construction equipment.
LTL – Less-Than-Truckload. Carrying less cargo than a full truckload weight for a customer. This includes shipping one package or half of a truckload.
LTL Carrier – A company that specializes in combining smaller shipments for multiple customers on one truck.

M

North American Transportation Management Institutehttps://www.natmi.org/

O

OTR – Over-the-Road. Long-haul trucking, as opposed to local or regional.
Owner-Operator – Trucker who owns or leases and operates his own truck(s).

P

P&D – Pickup and delivery.
Payload – Cargo weight.
Pintle Hook – Used to connect doubles and triples.
Private Carrier – A fleet that specializes in carrying goods for its own company.
PSI – Pounds Per Square Inch. Used to measure pressure in the tires and air brake system.
PSP Report – Pre-Employment Screening Program. A PSP record displays the motor carrier for which the driver was operating for at the time of the crash or inspection.
PTDI – Professional Truck Driver Institute. This organization certifies truck driver training programs. It does not teach CDL classes.

Q

Qualcomm – A wireless communication system that carriers use to keep in touch with drivers. It’s like a combination of GPS, email and text messaging. The system helps the company keep track of its trucks and it helps drivers know the status of their next load and the weather.

R

Reefer – Refrigerated trailer that has a cooling unit in the front and insulated walls. It’s like driving a giant freezer. These are usually used for perishable food items.
Relay – Two drivers start out in two different origin points several hours apart with loaded trucks. They meet in the middle, exchange cargo and return to their points of origin.
Retarder – Helps the brakes slow down the vehicle. Also Jakebrake.
RoadRailer – A trailer made to travel on both road and rail.
Runaway Ramp – Often seen on a steep grade, these are wide, soft areas a truck can pull into to slow down when its brakes lose power.

S

Shipping Weight – The weight of a truck not including the liquids like fuel and coolant.
Sleeper – A space to sleep behind the truck’s cab.
Sleeper Team – When two drivers work together so one can sleep while the other one drives, allowing freight to move as fast as possible while staying within federal hours of service regulations.
Sliding Fifth Wheel – A fifth wheel that can move back and forth to change weight distribution among axles.
Straight Truck – A one-piece truck with the cargo area attached to the chassis, as opposed to a tractor-trailer combination vehicle.

T

Team – When two drivers work together so one can sleep while the other one drives, allowing freight to move as fast as possible while staying within federal hours of service regulations.
TL – Truckload. A full trailer-load of freight.
TL Carrier – A trucking company that carries a single shipper’s freight on one truckload.
Tractor – A truck that is made to pull a trailer.
Tractor Trailer – A truck and trailer together.
Transfer Company – A firm that specializes in handling cross-border transactions.
Truck Driver Temp Services – Safety-minded staffing solutions to the commercial transportation industry.

U

Upper Coupler – Part of the connection between the tractor and trailer, it carries weight from the trailer, and houses the kingpin, which connects to the fifth wheel of the tractor.

V

VIN – Vehicle Identification Number. The manufacturer gives a unique VIN to every vehicle.

W

WIM – Weigh-In-Motion. A way to measure the weight of a vehicle as it rolls through a station, instead of making it come to a complete stop.