(Oklahoma Statutes, Title 47)
SUMMARY: Oklahoma is more than OK for vehicle modifications. The state doesn't legislate lifts or bumper heights. Allowable light heights are specified, and vehicles without rear fenders need mudflaps.
Headlamps (§47-12-203.B): Mounted not higher than 54 inches nor lower than 22.
Taillamps (§47-12-204.B): Mounted not higher than 72 inches nor lower than 15.
Auxiliary Lights (§47-12-217.E): Mounted not higher than 42 inches.
Mudflaps (§47-12-405.3): Vehicles without fenders over the rearmost wheels must have rubber or fabric aprons hanging perpendicularly to the body. Animal-drawn vehicles and farm tractors traveling less and 20 mph are exempt.
Oklahoma State Courts Network
This Ranger-bodied Bronco is licensable in South Dakota. (Almost everything is.)
(South Dakota Codified Laws, Title 32)
Summary: Improper light heights could incite citations in South Dakota. Vehicle heights cannot.
Taillights (§32-17-8): Mounted not higher than 72 inches nor lower than 15.
Auxiliary Lights (§32-17-17): Mounting heights range between 42 and 12 inches depending on light function.
South Dakota Legislature
Shot at the Memorial Day event in Dresser, Wisconsin, Fordzilla runs 48-inch Terra tires.
(Wisconsin statutes, chap. 347 & 348)
Summary: While most states limit bumper or frame heights, Wisconsin goes against the grain, capping lifts and tire heights: the maximum lift is 5 inches, and tires can be no taller than 8 inches over stock. That's for vehicles under 8,000 pounds GVWR. Vehicles over 8,000 pounds appear to be exempt.
Height Modifications (§347.455): "(2) If the modification is for the purpose of strengthening or improving handling, modifications may be made to the suspension system, axles, or chassis of a four-wheel-drive vehicle or a motor truck which has a gross weight of not more than 8,000 pounds which cause the vehicle to ride 5 or less inches above the height of the vehicle specified by the manufacturer. The height of the vehicle shall be measured from the level surface on which the vehicle stands.
"(3) A four-wheel-drive vehicle or a motor truck which has a gross weight of not more than 8,000 pounds may be modified to use a tire and wheel size which exceeds the wheel and tire size specified by the manufacturer for the vehicle by up to 4 inches in radius."
Headlamps (§347.09): Mounted not higher than 54 inches nor lower than 24.
Taillamps (§347.13): Mounted not higher than 72 inches nor lower than 20.