Chassis and Body
Most public fleet work vehicles are bought in two parts: a chassis from one manufacturer and a body or upfit from another. Two orders, two lead times, one delivery.
A refuse packer, a dump truck, an ambulance and a bucket truck are not bought whole. The agency buys a chassis and separately buys the body or equipment mounted on it, often from a different company entirely, with a third party sometimes doing the installation.
That split is the source of most delivery pain in a public fleet. The two orders have independent lead times and the total is not the longer of them but the sum: the body builder generally cannot start until the chassis arrives. A chassis delay pushes the body slot, and the body slot may not simply resume where it left off.
It also splits responsibility in ways that matter later. Warranty on the chassis and warranty on the body are separate, and a fault at the interface between them is where a fleet discovers which is which. Getting that boundary written into the specification is easier than negotiating it after a failure.
Procurement practice varies: some agencies buy chassis and body under one solicitation with a single point of accountability, some buy them separately for price. The single-award route usually costs a little more and removes an entire category of argument.
