Michelin is urging fleets not to change tyres prematurely, claiming it will cost businesses money and increase carbon emissions.

Research carried out by the French tyre giant found that changing tyres with 3mm of tread left instead of 1.6mm – the legal minimum – would cost EU drivers an extra £6.9bn a year in extra tyre purchases and additional fuel consumption, through increased friction on the road surface.

It would result in 128 million more tyres being bought a year in Europe, causing nine million more tonnes of CO2 emissions through the associated enviromental impact of producing more tyres and the aforementioned friction increases.

In addition, Michelin said it could not see a correlation between a decreased tread depth and increasing accident rates.

The firm likened changing tyres early to throwing away shoes because they needed to be cleaned, or putting a half-full tube of toothpaste in the bin.

To combat misconceptions about early tyre changes, Michelin is calling on tyre-testing bodies to compare and test tyres when they are worn to the legal limit instead of brand new, as they are tested at present.

According to research carried out on a test track in France by the tyre maker, dry weather braking distances improved marginally when the tyres were worn, while it claimed tyre noise levels are also reduced as the usage increases.

In terms of wet weather testing, the firm also found tyre performance improved as the wear increased.

“There is no consideration given to how their levels of performance will change over time. Michelin is now raising this issue – the fact that the only factor for safety is tyre performance – not tread depth. Michelin is calling on industry test bodies and consumer organisations to start comparing and testing tyres when they are worn to the legal limit,” Michelin said in a statement.

Michelin’s advice goes against that of fast-fitter Kwik-Fit, which urged fleets to follow the lead of UK emergency services by changing tyres well before the 1.6mm threshold.

According to results of a Freedom of Information request made by Kwik Fit, 73% of the UK’s police, fire and ambulance services change tyres at a tread between 2.6 and 3.0mm.

Of the 95 units that responded to the FoI request, 73% have a formal tyre-change policy in place, while the remaining third have an accepted practice on when to switch rubber.

“Our research has shown that the emergency services uniformly change their vehicle tyres at a much earlier point than the legal limit as a tyre’s performance starts to deteriorate well before it becomes illegal. When on a ‘blue light’ call our emergency services cannot compromise on safety, but we don’t think any other motorist should either, whether it’s a motorway run or just a trip to the shops,” said Roger Griggs, communications director at Kwik- Fit.