â¿¿ About 1.2 million Grand Cherokees from the 1999 to 2004 model years will be part of the "customer service action." Owners will get notices saying their vehicles are fine if they have factory or Chrysler trailer hitches. Dealers will inspect other trailer hitches to make sure they're secure. But if the Jeeps don't have trailer hitches, Chrysler won't do anything, maintaining that the Jeeps are safe and do not need any changes. A Chrysler spokesman was not sure how many of the SUVs are without trailer hitches.In a letter to Chrysler dated June 3, NHTSA's Office of Defects Investigation told the company all of the Jeeps should be recalled. "The defects present an unreasonable risk to motor vehicles," the letter said, "because people ... have burned to death in rear impact crashes." NHTSA began investigating the Jeeps at the request of the Center for Auto Safety, a Washington, D.C.-based advocacy group, that also says all the Jeeps should be recalled. "In view of Chrysler's refusal to recall 1999-04 Grand Cherokees, we call on NHTSA to move to an initial determination of a defect in order to force their recall as well," Clarence Ditlow, the center's director, said in a statement late Tuesday. Ditlow also said NHTSA should test the trailer hitches to make sure they protect the gas tanks. An agency spokeswoman said Tuesday evening that she was checking into details of the recall. Chrysler Group LLC, which is majority owned by Fiat SpA of Italy, wouldn't say how much the hitches would cost, although they sell for about $200 each on websites. Erik Gordon, a law and marketing professor at the University of Michigan, said Chrysler realized it was headed for a public-relations disaster and decided to reverse course. "What happened is they get surprised by how loud the hue and cry is," Gordon said.