The federal government shutdown could start affecting vehicle sales in a big way.

Not because its agencies and employees don’t have the money to buy them, but because they’re not at work to certify new models for sale.

Fiat Chrysler CEO Mike Manley told The Detroit News that the shutdown has stalled EPA approval for one of the new heavy duty pickups it revealed at the Detroit Auto Show this week.

Ram is planning to put the important models on sale this spring, and has the greenlight to sell the Ram 2500 truck, but the Ram 3500 that made headlines with the most powerful pickup engine ever has yet to have its papers stamped.

The EPA might not even need to conduct its own testing on the trucks. Automakers submit their own internal results for approval, and the agency only spot-checks 10 to 15 percent of them with its own evaluations. However, diesel vehicles like the Ram 3500 have been targeted for increased scrutiny after several automakers, including Fiat Chrysler, have been cited for emissions violations in recent years.

Heavy Duty trucks account for over a quarter of Ram’s pickup sales, and the automaker is hoping to leverage the buzz created by the Ram 3500’s segment-leading 35,100-pound towing rating before General Motors introduces its new updated HD models later in the year.

GM confirmed to the newspaper that a number of its 2020 models are also being held up by the EPA process, but declined to reveal which ones.

Ford would not comment on the topic.