Maintenance & inspection
What is bodywork and coupling?
Bodywork and coupling covers the structural condition of the vehicle and, for articulated combinations, the security of the connection between unit and trailer.
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<img src="https://fleetoptix.co.uk/glossary/bodywork/diagram.svg" alt="bodywork and coupling — diagram from FleetOptix" width="880" height="620" loading="lazy">
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<a href="https://fleetoptix.co.uk/glossary/bodywork">What is bodywork and coupling?</a> — diagram by
<a href="https://fleetoptix.co.uk">FleetOptix</a>
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</figure>The coupling is the highest-consequence item on the check. A trailer that separates is not a defect, it is a catastrophe, and the visual and physical checks exist because the failure mode is sudden.
Air and electrical lines between unit and trailer sit alongside the coupling itself, and they are the part most often damaged by routine coupling and uncoupling.
Bodywork matters for what it can shed. Loose panels, insecure doors and damaged fittings become road debris at speed.
What goes wrong in practice
- Coupling checked visually without the physical tug test.
- Susie lines damaged or dragging and treated as cosmetic.
- Body damage reported only when it becomes an obvious hole.