D7

This GMC designation refers to one of the brand’s medium-duty truck chassis codes, used for heavy vocational trucks rather than a consumer-facing nameplate. It appears in GM’s VIN documentation at the start of the 2000 model year for the 7000 Series and remains listed through the 2009 model year, when it is shown within the 7500 Series medium-duty lineup. In practice, it identified chassis-only and related commercial configurations built for body upfitters, such as dump, service, and other work-truck applications. The code belonged to the larger GM medium-duty family that included several closely related chassis and cab combinations, and it was part of the long-running General Motors commercial-truck program that served fleet and vocational buyers. After 2009, this particular GMC medium-duty designation was no longer carried forward under the same naming structure.