The manufacturer says there is no link between tread depths at 1.6mm and increasing accident rates. In addition, changing tyres at 3mm would cost the motorist money and increase carbon emissions - especially as a tyre becomes more fuel-efficient as it wears.
An Ernst & Young report commissioned by Michelin found that changing tyres at 3mm instead of 1.6mm would cost European Union drivers an extra 6.9 billion euros (RM33bil) a year in unnecessary tyre purchases and additional fuel consumption.
Instead, Michelin is calling for a change to the tyre testing regime to reflect wet braking performance at 1.6mm.
Tyres do not perform the same when new – and as a tyre wears, and the tread depth reduces, the difference in performance will change, and differences may be accentuated. This is because tyre performance is affected by many individual characteristics; casing design, materials used, rubber compounds, tread design, shape of grooves and sipes etc. Modern tyre technology makes it possible to provide high levels of performance and grip from new, and through all of the tyre’s life down to the legal tread wear limit.
Changing tyres early (i.e. before they are fully worn) does not guarantee greater safety, and no current studies have established a direct link between accident levels and tyre tread depth. Suggesting that tyres need to be changed early (before the legal limit / tread wear indicator is reached) is akin to enforcing a form of planned obsolescence.
The good news for motorists is that as long as tyres are not damaged in any way, the safety on dry roads actually improves as their tyres get worn.
As tyre tread depth reduces, the fuel economy of the vehicle will also improve, and with one tank of fuel in five being used to simply overcome the rolling resistance of the vehicles tyres, this is a welcome benefit.