can't really void your warranty.
if you replace your exhaust with an aftermarket exhaust, then obviously the exhaust is no longer warranted. that doesn't mean that the drivetrain is also voided tho.
if you repaint your panels, then the original paint job probably won't be covered anymore.
if you put in new springs and other suspension components, then your suspension won't be covered to the same degree anymore.
it's generally what you "upgrade" or "replace" that will be affected by the manufacturer's warranty.
nothing really voids the warranty in it's entirety.