Modes of Transportation - In an Automobile

Hellaflush: Prohibited in Québec

Hellaflush is prohibited in Québec. It refers to cosmetic modifications that are detrimental to a vehicle's handling and manoeuvrability.

What is hellaflush?

Hellaflush involves:

  • significantly lowering a vehicle's suspension
  • installing oversized and offset rims (offset is greater than that of the stock rims)
  • installing tires that are too narrow for the rim (tire stretching)

These modifications, which change the vehicle's suspension geometry, are usually noticeable because of the exaggerated negative camber.

Why is hellaflush prohibited?

Changes to the suspension geometry

Most lowered vehicles show incorrect camberInclination of a wheel, as viewed from the front or the rear of the vehicle, from its vertical axis. Camber is negative where the top of the wheel leans inward towards the vehicle. Camber is positive where the top of the wheel leans towards the outside of the vehicle..

Many vehicle models do not provide for camber adjustments, which makes it impossible to align the wheels in accordance with the vehicle manufacturers specifications after it has been lowered.

To compensate, the suspension must work outside the range for which it was designed, thereby reducing the vehicle's manoeuvrability and stability as well as tire surface contact with the road.

To know whether a modification is considered hellaflush

Alignment must be within the ranges specified by the vehicle manufacturer.

Under normal conditions, there should be:

  • no contact between the tires and the vehicle
  • no contact between vehicle components and the ground
  • reasonable suspension travel (with no contact between components)

What is prohibited

  • Using suspension components that are too stiff or with an insufficient travel range
  • Modifying a vehicle to the point where the tires touch a vehicle component or part of its body touches the pavement under normal driving conditions
  • Using a combination of rims and tires that does not comply with the tire manufacturer's recommendations
  • Using flammable or high-pressure products to seat a tire on a rim

Tire stretching

Tire manufacturers determine the rim dimensions that can be used for each type of tire for maximum safety and performance. It is also recommended that tires be inflated to the pressure specified by the vehicle manufacturer. When installing a tire, never exceed the mounting pressure indicated on the sidewall.

An improper combination of tires and rims is dangerous

It compromises the safety of all road users for the following reasons:

  • It causes flexing of the tire in places for which it was not designed. Since stretching obstructs the natural movement of the sidewall and tread, the tire must withstand considerable strain that could increase its temperature.
  • It reduces the tire's contact patch, which reduces traction and deteriorates performance and behaviour on the road.
  • It increases the risk of tire failure and the tendency for the tire to come off the rim.
  • It increases the risk of internal deformation of the tire (invisible from the outside), which can lead to its destruction.
  • It accelerates tire deterioration by overloading a tire with a lower load rating, which results in premature and inconsistent wear of the tire's tread.

Insurance, hellaflush and non-compliant modifications

Some insurance companies refuse to compensate claimants if it is shown that their vehicle has been modified using non-compliant components.

Oversized and offset rims

Because the space inside the wheel well is limited by mechanical components (suspension, steering, brake system, etc.), installing wider wheels requires a greater offset.

As a result, the extra size is pushed outward. This generally puts additional strain on the suspension and steering components and increases the lever effect between the wheel and the bearings, since the wheel is further away from its normal point of support. This additional strain will eventually:

  • cause a change in the axle camber
  • reduce vehicle stability
  • cause premature wear of the tires and other driving and suspension components

Using wider rims sometimes requires body modifications. To avoid this, some people install narrow tires that are stretched to the maximum. However, installing an offset rim that protrudes from the fender with the tire tread completely inside the wheel well is dangerous.

This practice is prohibited, since all road vehicles must be equipped with tires that are installed in compliance with established standards.

To know more

Contact your tire vendor or the Tire and Rim Association Web site.