A money saving tyre trick that could kill. Why an old winter tyre is a bad idea for a summer road trip
The spring tyre change season is officially over, yet plenty of cars still roll around on winter tyres. “I will finish off the old set this summer and buy new ones in autumn,” is the kind of sentence many car owners say with dangerous confidence.
For a few kilometres to the shop and back, that logic can seem almost sensible. For a proper summer road trip, with long distances, hot asphalt, sudden storms and a fully loaded car, it turns from thrift into a safety risk.
Long motorway runs, high temperatures and a heavy family car create exactly the conditions in which a winter tyre starts to lose the job it was designed to do.
Tests show hot asphalt turns winter tyres soft
Heat is the biggest enemy on a long summer drive. The rubber compound in a winter tyre is designed to work in freezing temperatures. Put that same tyre on summer asphalt, where the surface temperature can climb above 40 degrees Celsius in the sun, and the compound becomes too soft.
This is not just theory. Tests by motoring organisations such as ADAC and traffic research institutes point to the same problem.
The first issue is braking distance. On a summer road surface, braking from 100 km/h on winter tyres can take up to 16 metres longer than on new summer tyres. That is roughly three to four car lengths. In an emergency on the motorway, those metres can decide whether you stop in time or arrive hard in the back of the car ahead.
The second problem is steering response. In an avoidance test, a car on winter tyres loses composure much earlier. It reacts late to steering input, starts to feel vague and floating, and the rear can step out more easily than expected.
Then comes aquaplaning. In a summer downpour, water collects in deep ruts on the road. A winter tyre tread is dense and designed to handle snow and slush, not large volumes of standing water. A worn winter tyre can lose contact with the road already at around 70 to 80 km/h, while a proper summer tyre keeps working far more securely at motorway speeds.
The fuel saving myth
Many drivers defend the idea of using up old winter tyres in summer as a way to save money. Physics is less sympathetic. Long summer motorway journeys on old winter tyres can cost you at the fuel pump.
Because the rubber is softer and the tread blocks move more on warm asphalt, rolling resistance rises noticeably. Independent measurements show that driving on winter tyres in summer can increase fuel consumption by an average of 3% to 5%.
Load the car with holiday luggage and drive long distances at 110 to 120 km/h, and the penalty can climb towards 8%. On a longer trip, that means paying for several tanks of fuel simply to turn energy into heat and tyre wear.
No other choice? How to reduce the risk
Money can be tight, and sometimes buying summer tyres simply is not possible. When an old set of winter tyres really is the only option for a summer journey, the driver must change the way they drive.
Check the tyre pressure before setting off, especially with a fully loaded car. Use the maximum pressure recommended by the manufacturer for a loaded vehicle, usually shown on a sticker in the driver’s door frame. Higher pressure makes the soft tyre structure slightly firmer, reduces overheating on the motorway and improves stability and fuel consumption.
Leave far more space than usual. Since your braking distance is much longer, the gap to the car in front should be at least twice what you would normally leave. Those extra seconds matter.
Slow down hard in heavy rain. Do not try to hold the speed limit through a summer downpour. The aquaplaning threshold is lower on old winter tyres. Drop to 70 or 80 km/h and avoid deep water filled ruts where possible.
Take corners and overtakes calmly. Forget sharp steering inputs. A soft tyre does not like sudden changes of direction. Plan overtakes early, keep the car settled and drive through bends smoothly.
Saving money in the wrong place
Trying to save a few hundred euros by taking a hot summer family trip on old winter tyres is a classic false economy. Higher fuel use eats away at the saving, while the safety risks are very real.
When circumstances leave no alternative, conscious tyre pressure, longer gaps and a much calmer driving style become your only real insurance. Old winter tyres may still look usable in the driveway. On a hot summer motorway, they can be much less forgiving.
