leather seat cracking
Are you already out of warranty?? (not sure what the seat warranty is, never looked)
What has the dealership said about it?
Are they truly cracking or exhibiting normal creasing?
Yeah, I would think the leather would be covered by your 3/36 warranty. If your Lexus is more than 3 or 36K, replace/repair is on you. Your dealership might replace the seat covers as a goodwill gesture.