PACCAR designs and manufactures heavy-duty trucks under the Kenworth, Peterbilt and DAF brands, selling primarily to trucking fleets and owner-operators who move freight across North America and Europe. Truck demand is closely tied to freight volumes and the broader trucking industry's replacement cycle, since fleets typically retire and replace trucks on a fairly predictable schedule tied to mileage and maintenance costs. The company also operates a financial services arm that provides financing and leasing to truck buyers, and a parts business selling replacement components to the large installed base of trucks already on the road. PACCAR has invested in developing electric and alternative-fuel trucks alongside its traditional diesel lineup, positioning itself for tightening emissions regulations even as diesel trucks remain the large majority of its sales today.