I lost my key to my 1998 S500. The dealership said NLA, so I order a new
tumbler. I have not put it in yet, will the new tumbler with the new key
It will once you get them programmed to the car. Be prepared to have it towed or an auto locksmith to come out to the car. I would have the locksmith just cut you a new key if they can and program it. cheaper than replacing the tumbler.