VIENID Start practicing

Home › Lessons › Automobile Transportation

Truck Body Types, Cargo Loading Methods, Lashing, and Preventing Load Shift

Automobile Transportation · 自動車運送業 · Written by Tokutei Pass based on the official study texts; not copied verbatim.

Truck Body Types (Van, Wing, Flatbed, Refrigerated) and Green-Plate Responsibilities

The motor truck cargo transport industry receives freight charges from shippers and uses commercial trucks (green plates; black plates for light cargo vehicles) to deliver goods safely and reliably, serving as a vital backbone of Japan's logistics and economy.

Truck cargo beds come in various body styles depending on use: open 'flatbeds (hira-body)' suit overhead crane loading and long items, while enclosed 'box vans (van-body)' protect cargo from rain, wind, and theft.

'Wing-body' trucks whose side panels open upward like bird wings are widely used because they allow easy forklift pallet loading from either side; however, before opening the wings you must always check above and around the truck for signs, overhead wires, or low roofs.

Before driving off, always verify that the wing panels, rear barn doors, or flatbed side gates (aori) are completely closed and latched. Driving with unlatched wings or doors causes falling cargo and severe collisions with pedestrians or structures.

Furthermore, because trucks are much larger and taller than passenger cars, drivers must always keep in mind how dramatically braking distance and center-of-gravity height change between an empty truck (kusha) and a loaded truck (jissha).

Truck Body Types (Van, Wing, Flatbed, Refrigerated) and Green-Plate Responsibilities

Key points


  • Before opening or closing wing-body panels, check overhead and around the vehicle for wires, roofs, or signs

  • Always verify before departure that wing panels, rear doors, and side gates (aori) are securely locked

  • Keep in mind the major differences in braking distance and center of gravity between empty (kusha) and loaded (jissha) conditions
WordMeaning
flatbed truck with drop sides
wing-body truck
drop-side gate / side board (of a flatbed)
loaded vehicle (carrying cargo or passengers)

Loading Limits (Weight, Length, Width, and Height) and Strict Prohibition of Overloading

The weight of cargo loaded onto a motor vehicle must never exceed the 'maximum payload capacity (saidai sekisairyo)' stated on the vehicle inspection certificate (shakensho) and displayed on the rear of the truck.

Under the Road Traffic Act Enforcement Order, cargo size limits in principle are: 'height of 3.8 m or less from the ground (4.1 m or less on designated height-cleared roads),' 'length up to 1.2 times vehicle length (protrusion no more than 1/10 of vehicle length),' and 'width up to 1.2 times vehicle width (protrusion on each side no more than 1/10 of vehicle width).'

'Overloading (kasekisai)' beyond maximum payload capacity drastically lengthens braking distance, raises the center of gravity to cause rollovers on curves, damages brakes, tires, and axles, and deteriorates roads and bridges.

Overloaded driving carries severe criminal and administrative penalties not only for the driver, but also for the transport operator and the shipper (under the Shipper Recommendation System).

If a shipper asks you at a pickup site to load cargo exceeding your truck's maximum payload capacity, never load it and depart on your own; immediately contact your Operation Manager for instructions such as dispatching an additional truck.

Key points


  • 'Overloading (kasekisai)' beyond maximum payload is a serious violation that lengthens braking distance and causes rollovers

  • The height limit is 3.8 m from the ground in principle (4.1 m on designated roads), alongside strict overhang limits

  • If a shipper requests overloading, refuse to depart overloaded and immediately contact the Operation Manager for instructions
WordMeaning
maximum payload capacity
overloading
motor vehicle inspection certificate (shakensho)
shipper / consignor

Basic Cargo Stowage Principles to Prevent Load Shift and Rollover (Low Center of Gravity & Balance)

Improperly stowing cargo on a truck allows road vibration, braking forces, or centrifugal force on curves to cause 'load shift / cargo collapse (nikuzure),' which not only damages goods but also destabilizes the truck and causes rollovers.

The first rule of loading is to 'place heavy cargo on the bottom and light cargo on top.' This keeps the vehicle's overall center of gravity as low as possible and prevents upper cargo from crushing boxes on the bottom layer.

The second rule is to 'distribute weight evenly across the cargo bed and pack tightly from the front bulkhead (headboard / torii) with no gaps.' Any gap between the cargo and the front wall allows the load to slam forward under hard braking.

Loading weight unevenly to the left or right ('off-center loading / katani') causes the truck to lean sharply toward the heavy side under centrifugal force on curves, easily leading to a rollover.

Furthermore, concentrating heavy cargo at the rear of the bed ('rear-heavy loading / ushironi') lifts weight off the front axle, making the steering wheel light and severely degrading steering stability and front-wheel grip.

Key points


  • Place heavy items on the bottom and light items on top to lower the center of gravity, packing tightly from the front wall

  • Uneven left-right loading ('katani') is a direct cause of rollover accidents on curves

  • Rear-heavy loading ('ushironi') is strictly prohibited because it reduces front-axle load and causes loss of steering control
WordMeaning
load shift / cargo collapse
center of gravity
uneven / off-center load (katani)
cushioning / dunnage material

Cargo Securing (Ratchet Lashing Belts, Ropes, Corner Protectors) and Tarping

Securing loaded cargo firmly to the truck bed using ropes, ratchet lashing belts, load locks (lashing bars), or wire cables so that it cannot shift or fall while driving is called 'cargo securing / lashing (kobaku).'

Before using lashing belts or ropes, always inspect them for fraying, cuts, or bent buckles, and place 'corner protectors (edge guards)' wherever a belt passes over the edge of cargo to prevent both box damage and belt cutting.

Whenever gaps remain between cargo items or the side walls, fill them with 'dunnage / cushioning materials (spacers, airbags, foam boards),' and always block cylindrical cargo or drums with 'wedges / chocks (hadome).'

When covering cargo on a flatbed truck with a tarpaulin ('tarping / shito-gake') to prevent rain damage or scattering, stretch the tarp tightly from the front (upwind) side so wind cannot get underneath, and fasten it securely to the hooks with rubber bands or ropes.

Even after starting your trip, road vibration can loosen ropes and lashing belts, so walk around the vehicle during rest stops to re-inspect the lashing and retighten ('mashi-jime') as needed.

Cargo Securing (Ratchet Lashing Belts, Ropes, Corner Protectors) and Tarping

Key points


  • Place 'corner protectors' between lashing belts/ropes and cargo edges to prevent cargo crushing and belt cutting

  • Fill gaps with dunnage/spacers and always apply wedges (hadome) to cylindrical cargo

  • Re-inspect cargo lashing during rest stops and retighten belts/ropes to counter loosening from road vibration
WordMeaning
cargo lashing / securing
ratchet lashing belt / tie-down strap
corner protector / edge guard
chock / wedge (for cylindrical cargo)

Pallet Stacking Patterns and Safe Handling of Roll Box Pallets (Cage Trolleys)

Methods for stacking cardboard boxes on a pallet include 'block stacking (column stacking)' where boxes face the same direction, and interlocking patterns that alternate box orientation by layer such as 'alternating row stacking,' 'pinwheel stacking,' and 'brick stacking.'

Because block stacking has high vertical compression strength but collapses easily under lateral sway, combine it with interlocking upper layers or wrap the pallet with stretch film to prevent load shift.

Avoid 'overhang stacking' where boxes protrude beyond the edge of the pallet, as overhanging boxes collide with adjacent pallets and get crushed or topple.

Because wheeled 'roll box pallets (cage trolleys / kago-sha)' are heavy and have a high center of gravity, move them by 'pushing' rather than pulling so you can see ahead, and grip the vertical frame bars from the inside so your fingers cannot be pinched against walls.

After loading roll box pallets onto the truck bed, firmly lock all caster wheel stoppers (brakes) and additionally secure the cages to the cargo bed walls with lashing belts and load bars.

Key points


  • Use interlocking stacking patterns and stretch film on pallets, and never let boxes overhang the pallet edges

  • Move roll box pallets (cage trolleys) by pushing so you can see ahead, gripping inside the frame to protect your hands

  • On the truck bed, lock all caster wheel stoppers on cage trolleys and secure them with lashing belts and bars
WordMeaning
alternating-row pallet stacking
brick-pattern stacking
roll box pallet (wheeled cage trolley)
stretch wrap film

Temperature Control in Refrigerated Trucks (Pre-Cooling & Airflow) and Special Cargo

On refrigerated and freezer trucks carrying food products, always perform 'pre-cooling (yorei)' by running the refrigeration unit in advance to cool the cargo compartment down to the specified temperature before loading.

Because a truck refrigeration unit is designed to maintain cargo temperature rather than rapidly cool warm goods, also verify before loading that the cargo itself has been properly pre-chilled.

When stowing cargo inside a refrigerated compartment, leave clearance below the ceiling so the cold-air outlets are not blocked, and maintain air channels along the walls and floor (T-rails) so cold air can circulate.

When transporting liquids (in tank trucks or liquid containers), liquid surging back and forth during braking or cornering ('sloshing phenomenon') extends braking distances and can tip the vehicle over, requiring extra-smooth speed control.

When transporting hazardous materials, poisonous substances, or heavy/oversized items, strictly comply with regulations on displaying warning placards ('Hazardous (Ki)' signs or red flags), carrying fire extinguishers and emergency Yellow Cards, and holding required qualifications.

Key points


  • Pre-cool (yorei) refrigerated compartments before loading and leave airflow channels so cold air can circulate

  • When hauling liquids, watch out for liquid surge ('sloshing') that can cause rollovers or longer braking distances

  • When hauling hazardous materials, strictly follow laws on warning placards, fire extinguishers, and emergency Yellow Cards
WordMeaning
pre-cooling
cold-air circulation
sloshing / liquid surge phenomenon
hazardous materials (hazmat)

Cargo Checking (Kenpin) at Pickup/Delivery and Preventing Careless Errors

Both when picking up cargo at a shipping site and when delivering it at the destination, always perform 'cargo checking / tallying (kenpin)' by matching the actual goods against the shipping invoice (okurijo) or loading manifest.

During inspection, point and call to verify: (1) item name and code, (2) quantity/piece count, (3) destination, (4) any exterior damage (crushed, torn, wet, or soiled boxes), and (5) handling care marks ('This Side Up (Tenchi Muyo),' 'Fragile,' 'Keep Dry,' etc.).

In particular, the care mark 'Tenchi Muyo' means 'Do NOT turn upside down (This Side Up)'; laying such cargo on its side or upside down will damage or spill the contents.

If you discover a dented or wet box or a quantity shortage during pickup inspection, do not load it as is; verify it on the spot with the shipper's staff, report to your Operation Manager, and record it on the shipping slip.

Failing to do so can result in the damage or shortage being blamed on transit handling; thorough pickup/delivery inspection and obtaining a signed receipt are fundamental duties of a professional truck driver.

Key points


  • At pickup and delivery, match the shipping slip against actual cargo to check item name, count, destination, and box condition

  • 'Tenchi Muyo' is a care mark meaning 'This Side Up—do not invert or lay flat'

  • If you find damage or a shortage at pickup, confirm it with the shipper before loading and report to the Operation Manager
WordMeaning
cargo inspection / tallying
shipping invoice / waybill
This Side Up / Do Not Invert
cargo damage / freight claim accident

Truck: Loading and Lashing

Practice this chapter in the app

Official references