Dispatch glossary

ABS stands for Anti-lock Braking System. When a driver brakes hard — especially on wet, icy, or loose surfaces — the wheels can stop turning and skid. ABS rapidly pulses the brakes to stop that from happening, letting the tires keep gripping the road so the driver can still steer.

For a commercial truck, that added control shortens the odds of a jackknife or a loss of steering in an emergency stop, which is why the system is standard safety equipment on modern tractors and trailers.

An authorized carrier is a trucking company that a shipper or broker has already checked out and cleared to move their loads. The approval usually means the carrier’s operating authority, insurance, and safety record have been verified ahead of time.

Working only with authorized carriers protects the freight owner: it lowers the risk of fraud, uninsured loss, or a load ending up with an unvetted party. It’s also part of why brokers guard against double brokering, where a load is handed off to a carrier that was never approved.

An axle is the shaft that links the wheels on either side of a truck or trailer and bears a share of the vehicle’s total load. A tractor-trailer has several axles spread along its length to distribute weight across the road.

How weight sits across the axles matters a lot in trucking, because each axle and axle group has a legal limit. Spreading a load correctly — sometimes by adjusting sliding tandems — is what keeps a truck legal at the scales.

Axle rating is the weight limit permitted on an axle, or on a set of axles grouped together. It exists to protect roads and bridges and to keep vehicles handling safely, so it’s enforced by law rather than left to the driver’s judgment.

Even when a truck’s total weight is legal, an uneven load can put too much on one axle group and fail inspection. That’s why drivers weigh their rigs and, if needed, shift the load or the tandems to bring every axle within its rating before hitting a weigh station.

A backhaul is the trip back toward a truck’s home base or next region after it has delivered a load. The goal is to book paying freight for that return leg rather than driving back empty.

Backhauls matter to a dispatcher’s bottom line: a truck that returns loaded earns on both directions of a trip, while one that runs back empty — a dead head — covers fuel and hours with no revenue. Finding good backhaul freight is a big part of keeping trucks profitable.

A base plate is the license plate a truck carries from its state of registration — its “base” state. For commercial vehicles that run across state lines, that plate ties into apportioned registration, where fees are shared among the states the truck operates in based on miles driven.

Along with the cab card, the base plate is part of proving a truck is properly registered to operate interstate. Dispatchers and drivers keep this paperwork current because expired or mismatched registration can sideline a truck at inspection.

Bobtail describes a tractor (the truck cab and engine unit) running down the road without a trailer hooked up. You’ll hear it when a driver is heading to a yard to pick up a trailer, or driving back after dropping one off.

Bobtailing earns no revenue — there’s no freight moving — so dispatchers try to minimize how far and how often a truck runs bobtail. A tractor also handles braking and traction differently without a trailer’s weight behind it, which is worth keeping in mind on slick roads.

BOL is short for Bill of Lading. It is the central piece of paperwork on almost every shipment, laying out the terms between the shipper and the carrier and describing the load itself — commodity, weight, piece count, and the pickup and delivery details.

The document is typically signed by the parties involved as proof that the handoff happened, so it works as both a contract and a receipt. Dispatchers rely on an accurate BOL because it backs up billing, resolves disputes, and travels with the freight from pickup to delivery.

Bulk freight is cargo moved in large volume without individual packaging. Instead of pallets or cartons, it travels as a mass of material — dry goods like sand, grain, or cement, or liquids like gasoline and oil.

Because it isn’t packaged, bulk freight needs specialized equipment matched to the commodity: a tanker for liquids, a hopper body for dry bulk that unloads from the bottom, and other purpose-built trailers. Loading and unloading is usually done by pumping, pouring, or gravity rather than by hand.

A cab card is a registration document kept in the truck that shows the vehicle is legally registered to run interstate — including which states or Canadian provinces its apportioned registration covers. It’s essentially the proof that goes with the base plate.

Inspectors can ask to see the cab card, so drivers keep it in the cab at all times. Missing or expired registration paperwork is a common way for a truck to get held up at a weigh station or roadside check.

CARB stands for the California Air Resources Board, a state agency focused on cutting air pollution and protecting public health by setting and enforcing air-quality standards. Its reach is well known in trucking because several of its rules apply to commercial vehicles.

Trucks operating in California generally have to meet CARB emissions requirements, which can affect engine model years, equipment, and registration. Dispatchers routing trucks into the state pay attention to CARB compliance so a non-compliant truck doesn’t get turned away or fined.

Cargo is simply the goods a truck is carrying — the commodity being moved from pickup to delivery. In everyday use it’s interchangeable with freight.

What the cargo actually is drives a lot of decisions: the type of trailer needed, whether special handling or permits apply, how it’s insured, and how it’s valued on the paperwork. That’s why the commodity is always spelled out on documents like the bill of lading.

Cargo insurance protects the value of the load itself. If freight is damaged, stolen, or destroyed during transport, this coverage is what pays out on the resulting claim — as opposed to liability insurance, which covers harm the truck causes to others.

Shippers and brokers often require a carrier to carry a minimum amount of cargo coverage before handing over a load, and they’ll ask for a certificate of insurance as proof. It’s a basic condition of being trusted with valuable freight.

A carrier is the party that actually moves the freight — a trucking company or an owner-operator available for hire. Carriers range from a single truck to large fleets, and they haul either on the spot market or under ongoing contracts.

The carrier sits between the shipper (who owns the goods) and the receiver, and takes on responsibility for the load once it’s picked up. When a shipper or broker vets and approves one ahead of time, it becomes an authorized carrier for their freight.

CAT Scales are a widely used network of certified scales, usually found at truck stops, where a driver can weigh their truck and trailer for a small fee. Weighing before hitting the road lets a driver catch an overweight or unevenly loaded rig on their own terms.

A driver gets back a scale ticket showing the weight on each axle group, and can then shift the load or the tandems if any group is over its axle rating. It’s a way to avoid fines and failed inspections at an official weigh station.

CDL stands for Commercial Driver’s License. It’s the credential that authorizes someone to drive and operate heavy commercial vehicles like tractor- trailers, and it involves more testing and stricter standards than a regular driver’s license.

A base CDL can be extended with endorsements that permit specific work — hauling hazardous materials or operating tankers, for example. For a dispatcher, knowing which drivers hold which endorsements determines what loads each truck can legally be assigned.

The chassis is the underlying frame that holds a vehicle together — the engine, transmission, axles, cab, and cargo area are all attached to it. Think of it as the skeleton that everything else is built on.

The word comes up often in intermodal shipping too, where a “chassis” is the wheeled frame a shipping container is set onto so a truck can haul it. In both senses, it’s the base structure that makes the load roadworthy.

A claim is a request for money to cover a loss. Most often it’s a shipper seeking payment for freight that arrived damaged or went missing, but a carrier can also file a claim with its own insurance company after a wreck.

Documentation decides how a claim goes. The bill of lading and a signed proof of delivery establish what condition the freight was in and when, which is why dispatchers push drivers to note any damage at pickup and delivery rather than after the fact.

COI stands for Certificate of Insurance. It’s a formal document issued by an insurance company confirming that a particular business — a trucking company, for instance — currently carries coverage, and it lists the types and limits of that coverage.

Brokers and shippers routinely ask a carrier for a COI before releasing a load, using it to confirm the carrier holds adequate cargo and liability insurance. It’s a quick, standardized way to verify a carrier is properly protected.

The consignee is the person or company that receives a shipment. On the paperwork, they’re the receiving end of the delivery, and they’re the one who signs to confirm the freight showed up and in what condition. Consignee and “receiver” mean the same thing.

The consignee’s signature on the proof of delivery closes out the haul and is what lets the carrier bill for it. They sit opposite the consignor, the party that shipped the goods in the first place.

The consignor is the party that sends out the goods — the origin side of a shipment. In many cases the consignor is also the shipper, the one who owns the freight and arranges for it to be moved.

On the bill of lading, the consignor is named opposite the consignee, the party receiving the load. Knowing which is which keeps pickups and deliveries — and the paperwork trail — straight.

Dead head refers to distance a truck covers without earning freight revenue, most often an empty trailer repositioning to reach the next load. It still burns fuel, hours, and driver time, but nothing is being paid to move.

Because dead-head miles eat directly into a trip’s profit, dispatchers work to keep them low — pairing deliveries with a nearby backhaul so the truck reloads quickly. Tracking dead-head against loaded miles is also a useful measure of how efficiently a fleet is being routed.

A dedicated lane is a freight route that repeats on a regular basis — same origin and destination, same customer, similar product, on a predictable schedule. Instead of hunting for a new load every trip, a carrier commits to covering that lane consistently.

Dedicated lanes give both sides stability: the shipper knows capacity is covered, and the carrier gets steady, plannable revenue. Pairing a dedicated outbound run with a reliable backhaul is one of the cleaner ways to keep a truck earning in both directions.

Detention is money owed to the carrier when a truck sits waiting at a pickup or delivery beyond the free window it was given — usually because loading or unloading runs late. It compensates the carrier for the driver’s time and the tied-up equipment.

Detention is normally billed by the hour after the free time expires, and the amount depends on the agreement for that load. Dispatchers track it closely because unclaimed detention is lost revenue, and delays at one stop can cascade into missed appointments down the line.

A dock is the spot at a warehouse or distribution center where a truck backs up to have freight loaded or unloaded, usually at a raised platform that lines up with the trailer floor. Docks are the pinch point where a lot of a driver’s waiting happens.

If loading or unloading runs long past the free time, the delay can trigger detention charges. At busy facilities, a yard jockey shuffles trailers in and out of dock doors, and lumpers may be the ones physically handling the freight.

Double brokering happens when the party that booked a load re-brokers it to a different carrier without telling — or getting permission from — the shipper or original broker. Done deceptively, it’s a major red flag in freight and a common vehicle for fraud and non-payment.

The danger is that the freight ends up with an unvetted, uninsured carrier, and payment can vanish along the chain. It’s why shippers and brokers insist on working with authorized carriers and treat the rate confirmation as binding to the carrier that signed it.

Doubles refers to a setup where one tractor hauls two trailers hitched together — often two shorter “pup” trailers. Running doubles lets a carrier move more freight per driver, which is why it’s common in less-than-truckload and parcel networks.

Pulling doubles takes extra skill and, in the US, a specific endorsement on the driver’s commercial license. The combination is longer and handles differently, so not every driver or route is suited to it.

Drop and hook is a fast turnaround where a driver leaves one trailer at a facility and picks up another that’s already loaded and ready to go. Because the loading happened before the driver arrived, there’s little or no waiting at the dock.

This saves time and cuts down on detention, which is why high-volume shippers favor it. It relies on the driver properly setting the trailer’s landing gear and securing each connection so the swap is safe.

A dry van is the everyday enclosed box trailer — the most common type on the road. It hauls general, non-perishable freight that just needs to be protected from weather and theft, from packaged consumer goods to palletized products.

Because it’s so versatile and widely available, dry-van freight is the baseline of the trucking market. It contrasts with a reefer, which adds refrigeration, and a flatbed, which is open for oversized or awkward loads. Most dry vans close with either swing doors or a roll-up door.

A dual temp reefer is a refrigerated trailer built with two independently controlled temperature zones. A movable bulkhead splits the space so one section can run frozen while the other stays merely chilled, all in a single trailer.

This lets a carrier combine different perishable products — say frozen goods and fresh produce — on one load instead of needing two trucks. It’s a more specialized version of a standard reefer, and the added capability usually commands a premium.

ELD stands for Electronic Logging Device. It plugs into the truck and automatically tracks data like drive time, engine hours, speed, and miles, replacing the old paper logbook for recording a driver’s day.

Its main job is enforcing Hours of Service rules: because the ELD logs driving automatically, it’s much harder to run over legal limits without it being recorded. Most US commercial drivers are federally required to use one.

Endorsements are add-ons to a CDL that clear a driver for specialized work beyond a standard commercial vehicle. Each one requires additional testing — and sometimes a background check — before it’s granted.

Common examples include the hazmat endorsement for hauling hazardous materials, a tanker endorsement for liquid bulk in a tanker, and a doubles/triples endorsement for multiple trailers. For a dispatcher, a driver’s endorsements determine which loads that driver can legally be assigned.

An escort, or pilot car, is a vehicle that accompanies an oversized load to help it move safely through traffic. The escort makes sure the truck has room to navigate, watches for hazards like low bridges, and alerts other drivers that an unusually large load is coming.

Depending on the size of the load and state rules, one or more escorts may be required by permit, positioned ahead of and behind the truck. They’re a standard part of moving anything that exceeds normal legal dimensions, often alongside a heavy hauler.

ETA stands for Estimated Time of Arrival — the best current estimate of when a truck will reach a stop. It’s one of the most common updates a dispatcher gives to a broker, shipper, or receiver.

A reliable ETA keeps everyone coordinated: docks can plan labor, receivers can schedule appointments, and problems can be flagged early. It matters even more on a hot load, where the delivery is time-critical and a slipping ETA needs to be communicated right away.

An exempt carrier hauls freight that falls outside some of the usual federal economic regulations — typically because of the commodity involved (classic examples are unprocessed agricultural products) or the specific kind of movement. The exemption is about certain economic rules, not a free pass on safety.

Even when exempt from those requirements, carriers still have to meet safety standards under the FMCSA. The distinction mainly affects which authority and rules apply, compared with a standard for-hire authorized carrier.

Factoring is a way for a trucking company to get cash quickly. Instead of waiting 30, 60, or 90 days for a broker or shipper to pay an invoice, the carrier sells that invoice to a factoring company and receives most of the money immediately. The factoring company then collects the full amount from the payer and keeps a small fee.

For smaller carriers and owner-operators, factoring smooths out cash flow so fuel, payroll, and repairs can be covered without waiting on slow-paying customers. The trade-off is the discount taken on every invoice, so it’s a cost worth weighing against the value of faster payment.

FEMA is the Federal Emergency Management Agency, the government body that steps in to coordinate the federal response when a disaster overwhelms local and state resources — hurricanes, floods, wildfires, and the like.

It shows up in trucking because disaster response depends heavily on freight: water, supplies, generators, and equipment have to be moved fast into affected areas. These “FEMA loads” are often urgent, high-priority freight, closer to a hot load than routine work.

A flatbed is an open trailer — just a flat deck with no sides or roof. That openness makes it ideal for freight that can’t fit or be loaded into a closed box: lumber, steel, construction equipment, machinery, and cars.

Because the load is exposed, securing it correctly is the whole game. Straps, chains, and tarps hold and protect the freight, and loads that exceed legal size cross into oversized territory. For taller freight, a step deck offers a lower deck height.

FMCSA stands for the Federal Motor Carrier Safety Administration. It’s the branch of the US Department of Transportation focused on reducing crashes, injuries, and deaths involving large trucks and buses, through safety regulations and the systems that track carrier compliance.

A lot of everyday trucking rules trace back to the FMCSA — from Hours of Service limits to the authority a carrier operates under. It issues the MC Number and works alongside the USDOT registration that identifies commercial operators.

Freight is the general word for commercial goods in transit, no matter the mode moving them. When a dispatcher talks about booking, rating, or covering freight, they mean the loads themselves and the business of moving them.

It’s used interchangeably with cargo, and it spans everything from packaged consumer products to loose bulk freight. The type of freight determines the equipment, handling, and rate for a given load.

A fuel card is a specialized payment card for drivers to buy diesel and, in many cases, other on-the-road expenses. Fleets use them to control and track spending, and the cards frequently come with discounts at partner truck stops and fuel networks.

Beyond convenience, fuel cards give a fleet clean records of where and how much was spent, which feeds into cost tracking and settlements. Since fuel is one of the largest costs in trucking, even small per-gallon savings add up across a fleet.

A fuel surcharge is an additional fee layered onto the base rate of a load to account for changing fuel costs. Because diesel prices swing, separating this piece out lets rates stay fair to both carrier and customer as the market moves.

It’s usually spelled out on the rate confirmation and factored into the true rate per mile a load pays. When a dispatcher evaluates whether a load is worth taking, the fuel surcharge is part of the real revenue, not an afterthought.

Hazmat is short for hazardous materials — cargo like fuels, chemicals, explosives, or other dangerous goods that are federally controlled because of the risk they pose. Moving them comes with strict rules on labeling, paperwork, and handling.

Only a driver who holds a hazmat endorsement on their CDL — which requires extra testing and a background check — can legally haul it. Hazmat loads often pay more, reflecting the added qualifications, restrictions, and responsibility involved.

A heavy hauler is a rig purpose-built for extreme loads — the kind of weight or size a standard truck and trailer can’t legally or safely carry. These setups often use specialized multi-axle trailers to spread the load across the road.

Because the freight exceeds normal limits, heavy-haul moves typically need permits and one or more escorts, and they may be restricted to certain routes and times. This is the equipment behind most oversized loads — machinery, transformers, and other outsized cargo.

A hopper body is a trailer designed for dry bulk freight — grain, food products, dry cement mix, and similar loose materials. Its defining feature is bottom-unloading: gates or chutes underneath let the contents flow out by gravity.

That design makes loading and unloading quick and largely hands-off, which suits high-volume commodities. It’s the dry-goods counterpart to a tanker, which does the same job for liquids.

HOS stands for Hours of Service — the FMCSA rules that cap how many hours a commercial driver can be behind the wheel and on duty within a given window, and mandate rest breaks. The goal is to keep tired drivers off the road.

These limits shape everything a dispatcher plans, because a driver can only legally cover so many miles per day. Compliance is tracked automatically by the ELD, and running out of hours mid-trip can force a layover until the driver is legal to drive again.

A hot load is freight that needs to move right now — a time-critical delivery where speed is the whole point. Because the customer is willing to pay for that urgency, hot loads often carry a higher rate than routine freight.

For a dispatcher, a hot load means tighter coordination: a driver with available hours, a realistic ETA, and close communication so nothing slips. The urgency and the premium are usually reflected on the rate confirmation.

Intermodal shipping combines multiple transportation modes on one trip — commonly a container that travels by rail for the long haul and by truck for the first and last miles. The freight itself usually stays in the same container the whole way.

Trucks handle the drayage legs, moving the container between ramps, ports, and final destinations on a wheeled chassis. Where goods have to be shifted between containers or trailers, that step is a trans-load. Intermodal can lower cost on long routes by using rail for the heavy lifting.

Interstate trucking means a shipment travels between different states — pickup in one, delivery in another (or passing through several). It’s the opposite of intrastate, where everything stays within a single state.

The distinction matters for regulation: interstate carriers fall under federal FMCSA authority and rules, and need the corresponding operating authority and registration. Most long-haul US freight is interstate.

Intrastate trucking stays entirely inside one state — the pickup and delivery are both in the same state, with no crossing into another. It’s the counterpart to interstate freight.

The difference drives which rules apply. Intrastate operations are governed primarily by that state’s own regulations rather than the full federal framework, though safety standards still apply. Carriers need to know which category they fall into to hold the right authority.

A jackknife is when the trailer skids and swings out of line with the tractor, folding toward it at a sharp angle — the shape that gives the move its name. It usually happens on slippery roads or under hard braking when the trailer loses traction.

Jackknifes can cause serious crashes because the driver loses control of the combination. Safety systems like ABS help prevent the wheel lock-up that often triggers one, and careful braking on wet or icy roads is the first line of defense.

A kingpin lock is an anti-theft device that fits over the kingpin — the pin a tractor’s fifth wheel latches onto — of an unattended trailer. With the lock in place, no tractor can couple to the trailer, so it can’t be driven off.

It’s used whenever a loaded or empty trailer is left parked and unhooked for a while. Along with a numbered seal on the doors, it’s a common way to protect trailers and their freight from theft while sitting in a yard or lot.

Landing gear is the pair of crank-down legs beneath the front of a trailer. When the trailer is disconnected, the driver lowers them to support its weight; to hook up, they raise them back up so the trailer can roll.

Setting the landing gear correctly is essential during a drop and hook: if it’s not fully down or on solid ground, a parked trailer can tip or drop. It’s a small step drivers do constantly, and getting it wrong can damage the trailer or its freight.

A layover is an extended delay — typically overnight or around 24 hours — while a driver waits on part of a load, such as a delayed pickup or a delivery appointment the next morning. It ties up both the driver and the truck without moving freight.

Because it costs the carrier time and availability, a layover often comes with a fee, similar in spirit to detention but over a longer stretch. Layovers can also intersect with Hours of Service, when a driver has to stop until they’re legally rested to continue.

A lease is an agreement between an owner (the lessor) and a user (the lessee) for the use of a physical asset — in trucking, usually a tractor or trailer. The lessee pays to operate the equipment without buying it outright.

Leasing lets a carrier or driver run equipment without the full upfront cost of ownership. A related arrangement, the lease purchase agreement, adds the option to eventually buy the equipment — a path some owner-operators take into truck ownership.

A lease purchase agreement works like a regular lease but with a built-in path to ownership: when the contract ends, the lessee can buy the equipment. It’s a common way for a driver to work toward owning a truck without a large upfront purchase.

The appeal is becoming an owner-operator over time, with payments building toward the truck. The trade-off is that terms vary widely, so the real cost and conditions are worth reading closely before signing.

Liability insurance covers harm the carrier causes to others — for example, injuries or property damage from an accident the truck is responsible for. It protects third parties, and by extension the carrier, from the financial fallout of a crash.

It’s distinct from cargo insurance, which covers the freight being hauled. Carriers are required to carry liability coverage at set minimums, and they prove it to brokers and shippers with a certificate of insurance.

A logbook is where a driver’s time is recorded: hours spent driving, on duty but not driving, off duty, and resting in the sleeper berth. It’s the evidence that a driver is operating within legal limits.

Traditionally kept on paper, logbooks are now largely automated by the ELD, which captures driving time directly from the truck. Either way, the logbook is what enforcement checks against the Hours of Service rules during an inspection.

A lumper is a person — or a service — that handles the manual work of loading or unloading a trailer, usually at a warehouse or distribution center. Rather than the driver doing it, the receiving facility often uses lumpers to move freight at the dock.

Lumper fees are typically paid by the driver on the spot and then reimbursed, which makes them a routine line item in a dispatch operation’s accounting. Using lumpers can also speed up unloading and reduce the risk of detention from a slow dock.

An MC Number (Motor Carrier Number) is the operating-authority credential the FMCSA grants to a carrier, showing it’s authorized to move regulated freight across state lines for hire. It’s often used alongside — but is distinct from — the USDOT number.

Brokers and shippers check a carrier’s MC Number to confirm it holds active authority before trusting it with a load. Verifying it is part of qualifying an authorized carrier and guarding against fraud.

Mile markers are the numbered signs set at regular intervals along interstates and highways, counting the miles across a state. They give drivers a precise reference for where they are on a given road.

For trucking, they’re a practical shorthand: a driver can report a location, a breakdown, or a meeting point by mile marker, and a dispatcher knows exactly where that is. They also help estimate distance remaining to an exit or a stop.

A Notice of Assignment (NOA) is the document that formalizes a factoring relationship to the parties who owe money. It instructs brokers and shippers that the carrier’s invoices have been assigned to a factoring company, so payment should go to that company rather than to the carrier.

The NOA protects the factor’s right to collect and prevents payments from being misdirected. For a carrier that factors, making sure customers have the NOA on file is part of keeping the cash-flow process clean and getting invoices paid correctly.

An odometer is the gauge that records how many miles a vehicle has driven over its lifetime. On a commercial truck, it’s a basic but important figure — mileage drives maintenance schedules, resale value, and record-keeping.

Accurate mileage also feeds the numbers a dispatch operation runs on, from trip distances to the rate per mile math that decides whether a load pays. Odometer readings are a routine data point in tracking how hard a truck is being worked.

An oversized load is freight that’s too large or heavy to move under normal legal limits — too wide, tall, long, or heavy for a standard truck and trailer. Moving one legally requires permits, and often escorts and route or time restrictions.

These loads — construction equipment, machinery, prefab structures — usually ride on open equipment like a flatbed or step deck, or specialized heavy-haul trailers. The extra planning and permitting is why oversized freight typically pays more.

An owner-operator is a trucker who owns the truck they drive. They run the business side as well as the driving — either operating under their own authority (their own MC Number) or leasing on with a larger carrier and running under its authority.

Owner-operators carry the rewards and the risks of ownership: they keep more of each load’s revenue but cover fuel, maintenance, insurance, and payments themselves. Many reach ownership through a lease or lease purchase.

A partial is freight that doesn’t fill a whole trailer, so a carrier pairs it with other partial shipments to make up a full truck. Each customer pays for the portion of space and weight their goods take up.

Partials help fill capacity that would otherwise run empty, but they come with a trade-off: combining several shipments usually means multiple stops, so transit can take longer than a single point-to-point load. Dispatchers weigh the added revenue against the extra time and handling.

POD stands for Proof of Delivery. It’s the signed confirmation from the consignee that a shipment was delivered — noting that it arrived and whether it was in good condition. It closes the loop on a haul.

The POD is essential paperwork: it’s what lets the carrier bill for the load, and it’s key evidence if a damage or shortage claim comes up later. Along with the bill of lading, it forms the documentation trail for a completed shipment.

Pre-Pass is an electronic bypass system: an in-cab transponder lets participating trucks with good safety and credential records skip pulling into certain weigh stations, getting a green light to keep rolling.

Skipping stops saves time and fuel and keeps freight moving, which is why fleets value it. Some of these systems also handle electronic toll payment, bundling weigh-station bypass and tolling into one device.

A rate confirmation (often just “rate con”) is the paperwork a broker sends to lock in a load. It lays out the agreed rate along with the specifics of the job — pickup and delivery locations, dates and times, commodity, and any special requirements — and both sides treat it as the contract for that haul.

Dispatchers check the rate confirmation carefully before a driver rolls, because it’s the reference point if anything is disputed later: the rate that gets invoiced, the appointment times, and terms like detention all trace back to what’s written on it.

A reefer is a refrigerated trailer — the name is short for “refrigeration unit.” It has its own cooling system that holds the cargo at a set temperature for the whole trip, which lets carriers move perishable freight like produce, meat, dairy, and medicine.

Reefer freight comes with extra responsibility: the temperature has to be set correctly and monitored, and a failure can spoil an entire load. That added care is why reefer loads often pay more than the same run in a plain dry van.

A roll-up door opens by rolling upward and coiling around a drum at the top of the trailer, much like a garage door. Because it doesn’t swing outward, it needs no clearance behind the trailer — handy when backed tight against a dock or parked in a cramped lot.

It’s a common choice on dry vans and reefers. The alternative is a swing door, which seals better and is sturdier but needs room to open. Each style trades off convenience against durability and seal.

RPM stands for Rate Per Mile — the freight rate divided by the miles of the trip. It’s one of the fastest ways to compare loads: a $2,000 load over 1,000 miles pays $2.00 per mile, and a dispatcher can weigh that against costs and other options at a glance.

RPM is most useful when it accounts for the full picture — including dead-head miles to reach the pickup and any fuel surcharge — rather than just the loaded, paid miles. Looking only at the headline rate can make a load look better than it really is.

SCAC stands for Standard Carrier Alpha Code — a short code of two to four letters assigned to a carrier to identify it uniquely in shipping systems and documents. It’s a quick, standardized way to reference a specific company.

SCACs show up in EDI transactions, bills of lading, and the systems shippers and intermodal partners use to route freight. It’s one of several identifiers a carrier carries, alongside its MC Number and USDOT number.

A scale ticket is the printed record from a certified scale showing what a truck weighs — typically broken down by axle group as well as the total. It’s the proof that a rig’s weight was measured and where it stands against legal limits.

Drivers get one when they weigh at CAT Scales or a similar certified scale, and use it to confirm every axle group is within its axle rating before facing an official weigh station. It can also document legal weight if a load is ever questioned.

A seal is a numbered security device — often a plastic or metal tag — locked onto a trailer’s doors after it’s loaded. Its unique number is recorded, so anyone along the way can tell whether the trailer has been opened since it was sealed.

An intact seal with a matching number is assurance that no one tampered with the cargo in transit. The number is typically noted on the bill of lading, and the consignee checks it against the paperwork before breaking the seal to unload.

The shipper is the origin of a load — the company or person that owns the goods (or is responsible for them) and sets up their transport. They’re the customer side of a haul, the one that needs freight moved.

The shipper hands off to the carrier that hauls the load and to the consignee that receives it, with the bill of lading documenting the whole arrangement. In many cases the shipper is also the consignor, the party the goods are sent from.

Sliding tandems are the trailer’s rear axle group mounted on rails so they can be repositioned forward or backward. Moving them changes how the load’s weight is shared between the trailer axles and the tractor’s drive axles.

This adjustment is a driver’s main tool for getting legal at the scales: if one axle group is over its axle rating, sliding the tandems can rebalance the weight without touching the freight. It’s a routine step before a weigh station when a load sits unevenly.

A step deck (also called a drop deck) is a variation on the flatbed with two deck levels: a short upper deck over the gooseneck and a longer, lower main deck behind it. That lower deck lets taller cargo ride while staying under legal height limits.

It’s the go-to when freight is too tall for a standard flatbed but doesn’t need full heavy-haul equipment. Like a flatbed, it’s open for side or top loading and is common for machinery and other tall or oversized items.

A strap is a heavy-duty tie-down, typically made of tough vinyl or polyester webbing with a ratchet, used to lash cargo firmly to a trailer. Properly tensioned straps keep a load from sliding, tipping, or falling off while the truck is moving.

They’re central to flatbed and step deck work, where open freight has to be secured against the road. How many straps, and where, depends on the weight and shape of the load — and cargo securement is itself a regulated safety requirement.

Swing doors are the two hinged doors at the back of a trailer that open outward from the middle. They seal tightly and are sturdy, which is why they’re standard on reefers, where keeping temperature in matters, and common on dry vans.

The trade-off versus a roll-up door is clearance: swing doors need open space behind the trailer to swing wide, which can be awkward in tight yards or when backed close to another vehicle. In exchange they give a better seal and hold up well.

A tanker is a sealed, tank-shaped trailer for moving liquids and other flowable bulk freight — gasoline, oil, chemicals, milk, water, and the like. It’s loaded and unloaded by pumping rather than by hand.

Tanker work takes special skill and, in the US, a tanker endorsement, partly because liquid sloshing inside the tank shifts the truck’s balance and changes how it handles. Hauling fuels or chemicals adds hazmat requirements on top. It’s the liquid counterpart to a dry hopper body.

A team is two drivers assigned to the same truck. While one drives, the other rests in the sleeper berth, then they swap — so the truck can keep rolling far more of the day than a single driver legally could.

Because each driver logs their own Hours of Service, a team can cover long distances much faster, which makes them well suited to urgent, long-haul, or hot loads. The trade-off is two drivers to pay, so teams are used where speed justifies the cost.

A toll is a charge to use a specific stretch of highway, bridge, or tunnel. For trucks, tolls are often higher than for cars because they scale with axles and weight, and they add up quickly on toll-heavy routes.

Fleets manage tolls with transponders or toll accounts — sometimes bundled into the same device as a Pre-Pass bypass — and track them as a trip cost. When a dispatcher compares routes, tolls factor into which one is actually cheaper once time and fuel are weighed in.

TONU stands for Truck Order Not Used. It applies when a shipper or broker books a truck, the carrier dispatches it to the pickup, and then the load is cancelled after the truck is already committed or on its way. Because the carrier gave up that capacity and burned time and fuel, a TONU fee compensates them for the wasted trip.

The amount is usually agreed in advance or spelled out on the rate confirmation. For a dispatcher, making sure a TONU actually gets billed matters — a last-minute cancellation still costs the fleet real money.

Towing is the act of one vehicle pulling another, most often when a truck is disabled by a breakdown or accident and can’t move under its own power. A tow truck hauls it to a repair shop or a safe location.

For a fleet, a tow is both an unplanned cost and a disruption — the truck is out of service and the load may need to be rescued or reassigned. Heavy-duty towing of a loaded tractor-trailer is specialized and expensive, which is one reason preventive maintenance matters so much.

Trans-loading is moving freight out of one piece of equipment and into another to keep a shipment going — for example, shifting goods from a shipping container into a truck trailer, or consolidating loads for the next leg.

It’s a common step in intermodal freight, where cargo changes modes along the way, and at warehouses that combine or redistribute loads. The handling happens at a dock or transfer facility, and each transfer adds a bit of time and handling risk.

A truck stop is a facility geared to the needs of commercial drivers: diesel lanes, truck parking, restrooms and showers, food, and often repair services and scales. It’s where drivers refuel, rest, and take care of the truck on a long run.

For a dispatcher, truck stops are practical waypoints in a trip plan — places a driver can park for a required break, weigh at CAT Scales, or fuel using a fuel card at a discount. Parking availability in particular can shape where a driver ends the day.

A TWIC card — Transportation Worker Identification Credential — is the federally issued ID needed to enter secure areas of ports and other facilities regulated under the Maritime Transportation Security Act. Getting one involves a background check.

For drivers, a TWIC matters when work involves picking up or delivering at ports — common in intermodal and container freight. A driver who holds one can access loads that others can’t, so it can open up more work, much like a specialized endorsement.

USDOT refers to the US Department of Transportation, the federal agency responsible for the country’s transportation system and its regulation. The FMCSA, which governs trucking safety, sits within it.

In everyday trucking, “USDOT number” is the unique ID assigned to a commercial carrier, used to track its safety record, inspections, and compliance. Paired with the MC Number, it identifies a carrier across federal systems and appears on the truck and its registration paperwork.

A vendor is any supplier a trucking business buys from — the companies providing fuel, tires, parts, repair work, insurance, software, and other goods or services that keep the operation running.

Managing vendors is part of running a fleet: costs, reliability, and terms across vendors all feed into the bottom line. Keeping clean records of vendor expenses also matters for tracking the true cost of operating each truck.

A VIN (Vehicle Identification Number) is the unique string the manufacturer assigns to each vehicle. No two vehicles share one, so it’s the definitive way to identify a specific truck or trailer.

The VIN ties a vehicle to its registration, title, insurance, and history, and appears throughout that paperwork — including alongside the base plate and cab card. It’s used for everything from registering the truck to ordering the right parts.

A violation is a failure to comply with DOT rules or traffic laws — anything from an Hours of Service breach or an equipment defect to a paperwork or weight problem. Violations are often written up during roadside inspections or at a weigh station.

Beyond any immediate fine, violations follow a carrier: they feed into FMCSA safety scores that brokers and shippers can see. A poor record can cost a carrier freight, so keeping violations low is both a safety and a business priority.

A weigh station is an official checkpoint, usually on major highways, where commercial trucks pull in to be weighed and, at times, inspected. It’s where weight limits and safety compliance are enforced by authorities.

A truck that’s overweight or over its axle rating can be fined or held until the load is corrected, which is why drivers check their weight at CAT Scales first and keep a scale ticket handy. Qualified trucks can sometimes skip the stop using Pre-Pass.

A yard jockey (also called a spotter or hostler) is a driver whose job is to move trailers around a distribution center’s yard — pulling them from parking to dock doors and back, using a specialized short-range yard truck.

Keeping trailers flowing to and from the docks is what lets a busy facility load and unload efficiently, and it supports fast drop and hook turnarounds for over-the-road drivers. It’s a role focused entirely on-site, not on the highway.