Truck demand is likely healthier than last year, but regulatory certainty and manufacturer capacity are a different story.

“The 2027 regulatory engine transition is clearly impacting order seasonality this year, but the underlying demand for new equipment remains robust, supported by strong spot rate momentum,” said Carter Vieth, research analyst at ACT Research. “Fleets are eager to replace aging equipment and prepare for cost increases on the horizon, but the lack of regulatory clarity is making it difficult for them to plan effectively.”

Order season disrupted: September typically marks the opening of order books for the upcoming model year, but the seasonal uptick was muted this year. Manufacturers had not fully opened their 2027 order boards, according to ACT, which disrupted normal seasonal patterns. OEMs are still finalizing pricing and production strategies for next year’s equipment. That uncertainty is driven mostly by EPA's pending NOx regulation.

OEM compliance strategies vary: September’s orders also captured original equipment manufacturers’ (OEMs’) evolving strategies for 2027 emissions regulations. 2027 engine production and pricing will vary depending on a manufacturer’s attitude toward nonconformance penalties and emissions credits—assuming nonconformance penalties remain in EPA’s final rule.

Pricing clarity needs a final rule: Because truck manufacturers are employing varying approaches—and the EPA has yet to issue its finalized rule on NOx standards—equipment pricing could be subject to change over the coming months. Analysts from both firms expect order intake over the next one to two months to remain subdued until the final regulatory terms are published and OEM strategies fixed.

“Truck and engine manufacturers have announced varying strategies for handling the emissions transition, and some have not yet made their plans clear,” Moyer said. “The final EPA rule could still materially alter the economics of these strategies. Higher NCPs would narrow the cost advantage of current-generation engines while lower NCPs would make that pathway more attractive. That major issue, along with other potential changes, could affect 2027 engine availability, fleet acquisition costs, and the mix of technologies ultimately selected.”