This issue never seems to die. We all agree the dealer won't LIKE it. If your intent is to be popular with dealers, don't try to buy a car with a credit card. But as has been said many times, dealers are contractually obligated to VISA/MC/AMEX to accept their cards. If you choose to complain, the credit card company will make them accept. They can't make them like it, but if you want to get the miles this way, you can.