Modes of Transportation

Modified Cars: What Is Allowed, What Is Prohibited

Before modifying your car, find out which modifications are allowed and which ones are prohibited to avoid problems.

What you should know

The SAAQ is responsible for ensuring that all vehicles used on the road are safe and comply with the Highway Safety Code and its attendant regulations.

Passenger vehicles may be modified to change their appearance or improve performance. However, modifications must comply with the law in order for the vehicle to be authorized for road use.

It is therefore important to check the procedure for modifying a vehicle to avoid any problems or fines.

Before modifying a car

Contact us to find out which modifications are allowed and which ones are prohibited.

  • By telephone
  • By mail:
    Direction générale de l’expertise légale et de la sécurité des véhicules
    Société de l'assurance automobile du Québec
    Case postale 19600, succursale Terminus
    Québec (Québec)  G1K 8J6


Parts – Use parts that are specifically designed for the vehicle and issued by recognized manufacturers who certify their compliance with road use.


  • Modified vehicles are intended for use on the road, not on a race track or on uneven terrain.
    • Some modifications would have very good results on a race track, but can reduce vehicle stability under certain road conditions (rain, bumpy surfaces, etc.).
  • A police officer who has doubts about the safety of a vehicle can order it to undergo a mechanical inspection, even if the SAAQ had already deemed the vehicle in compliance, because it might have been modified again since the last inspection. Furthermore, if the police officer notices modifications for which you cannot provide a certificate of inspection from the SAAQ, your vehicle could be taken off the road if the officer believes it necessary due to the nature of the modifications.
    • A mechanical inspection certificate and certificate of inspection are not proof of compliance that lasts forever! They only prove that the vehicle was compliant at the time of the inspections.

Modified vehicles

At any time, police officers may:

  • pull over a modified vehicle or a vehicle in poor condition
  • detect a violation and serve a statement of offence
  • order an inspection by a road vehicle inspection agent
  • order that a vehicle be taken off the road

During a mechanical inspection, if the agent notes that modifications hinder the vehicle's braking ability or stability or no longer meet Transport Canada’s standards, the vehicle's owner must produce a modified vehicle record and make the necessary changes. This is the case for all vehicles that have been lowered or lifted.

In some cases, we can request an engineer's report indicating that the vehicle's safety has not been compromised.

The vehicle will be authorized for road use only if:

  • we accept the modifications
  • we receive a valid mechanical inspection certificate, and a certificate of inspection has been given to you

Last update: May 27, 2022