The National Highway Traffic Safety Administration (NHTSA) isn’t used to carmakers saying no to its requests. But that’s exactly what Chrysler has just done.

After the NHTSA asked the nation’s third largest car maker — now owned by Italy’s Fiat (FIATY) —  to recall 2.7 million Jeep Grand Cherokees and Jeep Libertys over potentially dangerous gas tank designs, the company refused. Chrysler claims the gas tank design is widely used in other vehicles not subject to NHTSA recall requests, CNN Money notes

Concerns over the placement of gas tanks behind the rear axel in Jeep models arose after the Center for Auto Safety, a consumer advocacy group, pointed out more than 200 rear-end crashes resulting in fires involving Grand Cherokees and 36 more for Jeep Libertys. More than 300 deaths were linked to the accidents. The NHTSA has been looking into the accidents since 2010.

Chrysler says that most of the deadly accidents cited by the Center for Auto Safety involved high-speed impacts, which would have produced fires and death regardless of where the gas tanks were located.

Jeep Grand Cherokees made between 1993 and 2004 and Jeep Libertys made between 2002 and 2007 after affected by the NHTSA’s request. The company altered the gas tank design in more recent models.

This isn’t the first time Chrysler has challenged the NHTSA. In 1996, the company refused to recall 91,000 cars over possibly defective seat belts. A federal court later sided with Chrysler in that matter.

Shares of Fiat climbed almost 2% in over-the-counter trading on Wednesday.