North American Heavy Truck and Off-Highway Polymers: Supply Base and Application Map

North American heavy truck and off-highway polymer demand runs on a fraction of automotive volume. A strong Class 8 year is around 300,000 units across the whole market, a single tractor model may build 5,000 a year, and a construction cab program can run in the hundreds. That volume gap is the organizing fact of the industry. It decides which materials win, which processes are economic, and how much of the work stays inside the OEM.

Sheet molding compound is the signature material. Hoods, fenders, roof fairings, sleeper panels, and battery box covers are compression-molded SMC because a set of SMC tools costs a fraction of a stamping die set and still delivers a painted Class A surface. Polyurethane and pDCPD reaction injection molding carry the same logic down to the lowest volumes on tractor hoods, bumpers, and construction cab panels. Thermoformed ABS and TPO sheet fill the large, thin fairings and skirts.

Thermoplastic injection molding looks more like automotive underneath. Talc-filled PP dashboards, door panels, and HVAC cases, glass-filled PP air cleaner housings, glass-filled PA66 coolant tanks, and PC/ABS mirror housings draw on the same resin producers and compounders that serve light vehicles. Rotomolded HDPE takes DEF tanks, ag fenders, and cargo boxes where tooling has to be cheap.

Demand is concentrated in the Carolinas, Ohio, Texas, and the upper Midwest for trucks, and in Iowa, Illinois, Wisconsin, and Georgia for off-highway. Bus demand is smaller and concentrated in Georgia, North Carolina, Minnesota, and Manitoba.

The tier structure is the classic OEM, Tier 1, Tier 2, Tier 3 pyramid, but with more vertical integration than automotive and a much smaller cast at each level.

OEMs own cab design, paint, and final assembly, and several own composite molding as well. Deere and CNH mold panels in-house, and the truck OEMs keep paint and bonding of SMC hoods at the truck plant. What an OEM buys from a Tier 1 is a molded and often primed panel, a complete seat, an HVAC module, or a lighting assembly.

Tier 1 in this industry is a short list. Core Molding Technologies and Teijin Automotive Technologies mold most of the SMC exterior for Class 8, and both compound their own SMC, so they are simultaneously Tier 1 molder and Tier 2 material supplier. Molded Fiber Glass Companies plays the same role for off-highway. Commercial Vehicle Group, Grammer, and Bergstrom cover cab interior and HVAC. Modine and Donaldson own the glass-filled nylon and PP housings under the hood. Rotomolders such as Centro sit at Tier 1 for tanks and cargo boxes.

Tier 2 is materials: SMC resin from AOC, Polynt-Reichhold, and INEOS Composites, merchant SMC from IDI Composites, pDCPD from Metton, and thermoplastic resin and compounds from the same producers automotive uses, LyondellBasell, Celanese, BASF, Covestro, SABIC, Ascend, Avient, and RTP. Tier 3 is glass fiber, the same three producers as marine composites: Owens Corning, Johns Manville, and Jushi USA.

Distribution matters more here than in automotive. Nexeo Plastics, Chase Plastics, and Ravago Americas carry resin to the mid-size injection molders, and Composites One carries SMC and reinforcements to the small compression molders that serve off-highway and bus.

Three companies anchor demand by scale. Caterpillar is the largest, building construction and mining equipment in Illinois, Georgia, Texas, and North Carolina, with polymer content concentrated in operator cab panels, hoods, tanks, and interior trim. Deere & Company runs the largest agricultural program in North America from Iowa and Illinois, and is the reference customer for pDCPD and SMC hoods, rotomolded tanks, and Gator cargo boxes. Daimler Truck North America builds more Class 8 trucks than any other manufacturer on the continent, with Freightliner and Western Star assembled in the Carolinas, Oregon, and Mexico, and is the largest single buyer of SMC hoods, roof fairings, and sleeper panels.

Behind these three sit the remaining truck OEMs, PACCAR, International Motors, Volvo Trucks North America, and Mack Trucks, the off-highway group led by CNH Industrial, AGCO, Kubota, Komatsu America, Oshkosh, Doosan Bobcat, Terex, and JLG, and the bus builders Blue Bird, New Flyer, GILLIG, and Thomas Built Buses. The full roster with scale band, product scope, and plant footprint is in the gated portion of this report.