This medium-duty truck designation belonged to General Motors’ conventional commercial lineup and was used on the 4,500- and 5,500-series trucks built for vocational work rather than retail pickup duty. It sat in the work-truck portion of the brand’s lineup, serving fleets, upfitters, and commercial buyers who needed straight-frame chassis, cab-and-chassis configurations, and the durability expected from medium-duty equipment. The series was part of GM’s long-running medium-duty truck family that shared engineering and cab development with other commercial variants across the division’s truck portfolio.
In the early 2000s, the designation appeared in GM VIN and model-line documentation for the 5,500-series conventional truck, showing that it was in production by the 2000 model year and continuing through the end of the decade. The line was used on trucks commonly associated with medium-duty commercial applications such as municipal service, delivery, towing, and specialty body installations. GM later announced in 2009 that it would wind down medium-duty truck production, and the line was discontinued after that model year. Because there was no separate revival of this exact nameplate, it is treated here as one continuous production run from 2000 through 2009.