A guide to legal car modifications in Idaho
Auto repair

A guide to legal car modifications in Idaho

09.11.2022 /

ARENA Creative / Shutterstock.com

Whether you live in the state or plan to move there, Idaho has vehicle modification regulations that you must follow to ensure that your vehicle is considered road legal when you drive on the roads. The following information will help you make sure you know what you can do with your changes.

Sounds and noise

Idaho limits the levels of noise that vehicles can make from engine/exhaust systems and sound systems.

Audio system

There are no specific laws in Idaho regarding sound systems in vehicles, except that they cannot cause inconvenience or annoyance to those in a certain area, which is by nature subjective.

Muffler

  • Silencers are essential and must be in good working order.

  • Silencers cannot be modified to produce a sound louder than the manufacturer's original equipment.

  • Silencers cannot produce a sound louder than 96 decibels when measured at a distance of 20 inches and at a 45 degree angle from the exhaust pipe.

Functions: Also check your local Idaho laws to make sure you comply with any municipal noise ordinances that may be stricter than state laws.

Frame and suspension

In Idaho, the following vehicle frame and suspension regulations apply:

  • Vehicles cannot exceed 14 feet in height.

  • There is no restriction for the body lift kit as long as the vehicle is within its maximum bumper height for its gross vehicle weight (GVWR).

  • Vehicles up to 4,500 pounds have a maximum front bumper height of 24 inches and a rear bumper height of 26 inches.

  • Vehicles weighing 4,501 to 7,500 pounds have a maximum front bumper height of 27 inches and a rear bumper height of 29 inches.

  • Vehicles weighing between 7,501 and 10,000 pounds have a maximum front bumper height of 28 inches and a maximum rear bumper height of 30 inches.

  • 4×4 vehicles with a gross weight of less than 10,000 pounds have a maximum front bumper height of 30 inches and a rear bumper height of 31 inches.

  • Bumper height must be at least 4.5 inches.

ENGINES

Those who live in Canyon County and Kuna City, Idaho are required to undergo emissions testing. These are the only engine requirements in the entire state.

Lighting and windows

Lanterns

  • Blue lights are not allowed on passenger cars.
  • Two fog lights are allowed.
  • Two spotlights are allowed.

Window tinting

  • Non-reflective tinting can be applied above the manufacturer's AS-1 line.
  • Front side windows and rear glass must let in more than 35% of the light.
  • Rear side windows must let in more than 20% of the light.
  • Reflective and mirror shades cannot reflect more than 35%.

Vintage/classic car modifications

Idaho requires vehicles over 30 years old to have an Idaho Classics license plate. These vehicles may not be used for daily commuting or driving, but may be used in parades, tours, club events, and exhibitions.

If you want your vehicle modifications to comply with Idaho laws, AvtoTachki can provide mobile mechanics to help you install new parts. You can also ask our mechanics what modifications are best for your vehicle using our free online Ask a Mechanic Q&A system.

Add a comment