Doesn't it depend on whether the car is FWD or RWD?
Actually, no, according to the experts at Continental Tyres, who spend a lot of money learning about these things.
The new tyres should always be on the back end of the car, they say, and can dazzle you with the physics to show why.
Next question. Is it advisable to mix brands, especially when you have still have a decent amount of tread on the older tyres? Especially adding new but budget covers to save some money?
The best way of sorting that was by giving us a chance to try cars with different tyres setups, and put them into the kind of situations that will provoke reactions.
So we drove a pair of Minis around a tight circle, each shod differently. The circle was kept wet, to allow breakaway when the tyres lost adhesion as speed was gradually increased.
One car wore part-worn Continental premium tyres on the front, and a pair of new budget tyres on the rear. So the tread depth setup was 4mm Contis and 8mm budget.
When we drove that one we found that the car ran safely enough but the rear broke away suddenly when the speed and centrifugal forces increased.
Then we drove with an all-Continental setup, again the front ones part-worn and the rear ones new with full tread. This time the difference was marked, with the car holding firmly on the wet surface at speeds well beyond where the previous one had lost grip.
Although in a test situation, and in safe controlled circumstances, the experience was very true to life, and reflected a situation where a driver would be taking a sharp curve at speed, maybe on a cloverleaf motorway intersection.
It brought home to me once again the importance of keeping the best tyres you can afford under your car, and being sure that they are setup to gain the best possible safety while travelling.
