It can vary WIDELY depending on the particular vehicle in question, sure you aren't going to be able to lower a car as much as a full size truck.
You aren't going to need to lift a full size truck as much as a small truck to achieve the same effect.
THEN, there are those that would like to install 44 inch tires on a mini truck and run it on the streets, the main reason behind lift laws IMO.
UPDATE, after a short online search I found the following:
MO has a bumper height law:
Regular vehicle – 22” front and rear
Commercial vehicle up to 4500# – 24” front 26” rear
Commercial vehicle 4501-7500# – 27” front 29” rear
Commercial vehicle 7501-9000# – 28” front 30” rear
Last edited by M&M CUSTOM; 11-09-2009 at 04:49 PM.