DaimlerChrysler's hottest US seller - the retro-look Chrysler PT Cruiser - has finally hit a sales slump and the company is offering the first cash rebates, the Detroit News reported. The newspaper said that US PT Cruiser sales fell 36 percent to 8,600 vehicles in January and that Chrysler had responded by offering buyers - so far, only in the Midwest and Northeast - $US1,000 cashback deals.