DETROIT — More than half of the nearly 2,800 dealers General Motors and Chrysler want to close are appealing those decisions, the group handling the appeals said Tuesday.

The American Arbitration Association said 1,550 dealers filed the paperwork needed to contest the closures by the midnight Tuesday deadline. The group said the number could go higher as more appeals arrive in the mail.

Meanwhile, Chrysler is weighing a federal lawsuit to stop the appeals, with sources close to the automaker saying the appeals process could cost it hundreds of millions of dollars. The sources asked not to be identified because a decision hasn't been made.

The association didn't give a breakdown of the number of dealers appealing at each automaker. GM and Chrysler said they won't have exact numbers until later this week. Arbitration hearings are expected to begin in late February or early March and are supposed to be wrapped up by June 14.

Chrysler shut down 789 dealers in June in an effort to make the remaining dealers more profitable, although around 80 percent of them remain in business selling used cars or vehicles from other brands. GM has told 2,000 dealers it will revoke their franchises in October.

Congress passed a law last month requiring an appeals process for dealers.