Lay out the cargo inside the finished body
Start with the cargo units you actually carry: their packed dimensions, individual masses, support areas and stacking limits. Plot the expected maximum consignment on the deck, then check whether the forklift, crane or manual handling method can place and remove it.
Measure the usable length and width between finished internal faces with the sides closed. Show this cargo footprint separately from the space needed to lower the sideboards. Mark corner posts, hinges and other obstructions, and leave access to anchors and side latches. External body dimensions can make the available load space look more generous than it is.
Side height should suit handling reach, cargo type and containment. Taller sides do not establish a higher payload or a restraint rating. Show the floor height and the space needed to lower the sideboards, alongside route access and dimensional restrictions. HSE’s loading checklist is a useful UK reference for considering the load, delivery vehicle and handling equipment together. HSE: loading and unloading workplace checklist
For an initial shortlist, the linked KEEYAK deck references give light-duty length 3.3 to 4.2 m and width 1.6 to 2.1 m. Medium-duty references give 4 to 7.6 m and 2 to 2.45 m; heavy-duty references give 6.8 to 12 m and 2.3 to 2.5 m. Each pair describes a body family. It does not confirm the finished clear space, and the largest length and width are not necessarily available together.
Calculate the cargo allowance from the ready-for-work truck
The first mass check is permitted gross mass minus the mass of the truck in its agreed ready-for-work condition. That difference gives gross-mass headroom for cargo. A lower body or axle limit can still govern what the truck may carry.
Agree what the truck mass includes before doing the subtraction. Account for the body, fuel, driver and passengers, toolboxes, spare wheel, covers, securing equipment and delivery aids. If the supplier has already included an item, do not subtract it again; if it is excluded, add its allowance to the schedule.
Separate measured masses, calculated values and unresolved allowances. The final weighing record should identify the vehicle and its equipment, fuel and occupants or agreed allowances. This makes it possible to compare the finished truck with the estimate used for the order.
Check where the weight sits and how it reaches the floor
A half-empty deck can still have an overloaded axle. Moving a heavy item toward the rear changes the distribution even when total cargo mass stays the same. Have the supplier check the departure load, important partial-delivery arrangements and return loads.
The floor needs the contact loads as well as the total cargo mass. Pallet feet, stillage legs and narrow bundles put the load through different areas, and a material name alone cannot establish suitability. Include any handling equipment that will enter the body. A larger usable deck does not resolve a concentrated floor load or an overloaded axle.
A floor-load reference in t/m² expresses mass per area; 1 t equals 1,000 kg. It is different from a completed truck payload in tonnes. The catalog entry does not state the load distribution or support conditions, so multiplying it by deck area cannot establish a permitted cargo load. Use the offered floor specification to check concentrated pallet or wheel loads separately.
Scroll horizontally to view all columns.
| Check | Give the supplier | Request in the proposed configuration |
|---|---|---|
| Axle distribution | Cargo masses and positions at the relevant delivery stages | Gross and axle calculations for those arrangements |
| Floor contact loads | Support locations, contact areas and loads, including equipment entering the body | Confirmation of floor and mounting suitability for the declared loads |
| Body and chassis fit | Required body length and operating access | Wheelbase, rear overhang and mounting review, including site maneuvering |
Update the loading plan when the equipment changes
Adding a tail lift, crane or rack changes the truck you are assessing. Update the mass schedule, loading layout and quotation revision together. The earlier payload estimate no longer describes the new equipment list.
JC Payne’s dropside range shows how the body category serves different operations. A light-, medium- or heavy-duty label still cannot replace the dimensioned drawing and loading schedule for the offered truck. JC Payne: dropside bodies
Send the cargo dimensions, masses and full accessory list with the inquiry. Ask for a completed-body drawing showing internal deck dimensions, side heights and floor height; the mass and axle review; floor confirmation; and final weighing record. Give the operator a loading diagram with accepted cargo positions and restrictions.
Use these checks to establish usable space and the remaining cargo allowance together. The arithmetic is an inquiry framework, not a vehicle-specific load certification; the exact vehicle and destination determine the final limits.
Sources and applicability
Manufacturer examples of dropside bodies for general cargo, scaffolding and building-material delivery; individual body construction remains quotation-specific.
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UK workplace reference for planning loading areas, handling equipment and load security. Used to frame buyer questions, not to claim regulatory approval.
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