i don't think that Lexus dealer would do any mods for you, may be the most would be to put somethig TRD on your car . as far as waranty goes, Lexus are preaty cool about waranting stuff for you, especially if you do your maintnes with them. obviously the parts that you replace wont be waranty any more, so as if those parts couse failure of other parts, those other parts wont be warantiable any more, but thay may still do it, it all depends