General Motors announced last month that it would provide compensation to owners of their models of SUVs after admitting it had incorrectly calculated the fuel economy on the vehicles. But that apparently isn’t enough for some GM owners who have filed a potential class action against the carmaker. 

The lawsuit [PDF], filed in a federal court in San Diego, accuses GM of deceptively marketing, and advertising some Chevrolet Traverse, GMC Acadia, or Buick Enclave vehicles by overstating the gas mileage since at least 2009.

A California woman, who owns a 2016 Buick Enclave, alleges that she was enticed to purchase the vehicle through GM’s advertisements that included supposedly exaggerated gas mileage.

While GM admitted in May that it had overstated the gas mileage of the model year 2016 Chevrolet Traverse, GMC Acadia, or Buick Enclave, the new lawsuit claims that the same issues were found in additional model years, including those from 2009 to 2016.

“All of the Chevrolet Traverse, GMC Acadia, and Buick Enclave vehicles for model years 2009 to 2016 were represented to have the same inflated gas mileage,” the suit states. “Yet all have substantially the same engines, weights, sizes and shapes and, thus, should achieve substantially identical gas mileage.”

The suit alleges that GM has touted the inflated mileage in advertisements, its website, and in other materials for years, allowing the company to charge a premium for the vehicles.

In one case, GM represented that the 2009 to 2011 Enclave had “better highway fuel economy than any other eight-passenger crossover.”

The company also heavily promoted the fuel economy of the Chevrolet Traverse, marketing it as a vehicle that achieves both power and fuel efficiency.

As a result of the alleged unlawful conduct, “the class members have suffered harm in that they bought or leased vehicles they would not otherwise have bought or leased, or paid more for such vehicles than they otherwise would have.”

For example, the woman claims that prior to purchasing her Buick Enclave she was exposed to marketing materials, including GMs’ website, that touted the vehicle’s mileage.

“Plaintiff also discussed the vehicle’s gas mileage with the dealer,” the suit states. “Plaintiff acted in substantial part on material representations of GM regarding the fuel economy performance of the 2016 Buick Enclave, particularly when compared to other similar vehicles, when deciding whether to purchase the Enclave.”

The woman believes she was charged and paid a price premium for her vehicle based on the claim that it would achieve 17 miles per gallon in city driving, 24 mpg on highways, and a combined fuel economy of 19 mpg.

“Had GM disclosed the accurate fuel economy of the 2016 Buick Enclave, Plaintiff in all reasonable probability would not have purchased the Enclave or would have paid less for it,” the suit states.

In all, the suit claims that owners of affected vehicles will spend approximately $300 more per year than expected because of the mileage exaggeration, or more than $2,400 during the minimum useful life of such vehicles.

The lawsuit seeks to provide owners of affected vehicles with any proceeds obtained by GM as a result of the sale of the vehicles.

“We will oppose any effort by the plaintiffs’ bar to interfere with our effort to provide our customers the option to obtain timely compensation for our error,” a spokesperson for GM says.

Previously, GM alerted dealers that it would try to make it up to thousands of customers by providing them a prepaid gift card valued between $450 and $1,500 or an extended warranty.

Under the program, which began on May 25, customers who purchased a 2016 Chevrolet Traverse, GMC Acadia, or Buick Enclave can choose between a debit card or a 48-month/60,000-mile service protection plan that improves their existing factory warranty.

Those who leased one of the affected vehicles will be offered a debit card.

The value of the debit cards will be determined based on whether or not the vehicle was leased or owned, and what type of vehicle it is.

“We designed this reimbursement program to provide full and fair compensation in a simple, flexible and timely manner,” a GM spokesman said at the time the compensation was announced, apologizing to customers for the misstated labels.

Editor's Note: This article originally appeared on Consumerist.