Voiding of vehicle warranty would depend on several factors all of which are written on your warranty booklet. Take a glance. Just like what mikey177 has said most warranties are not void if your dealer is one who will install your preferred aftermarket accessory like in your case lowering of the car. There was a case a few years ago when owners of Mazda 323 Familia who later opted to upgrade their current cars to Mazda SPeed parts whose warranties where not void basta casa gagawa. (This includes their lowering springs by Eibach). It's advisable to ask your dealer first before installing or doing anything. :wink: