Where do the new tyres go?

Buying a pair of new tyres means having to choose where the new tyres go. We address the question and explain which axle to fit them to.

Tyre wear is not symmetrical. Weight distribution, the driven axle, and the type of use and driving style can mean that only two new tyres need to be fitted to a car. That is when the dilemma arises: where do the new tyres go?

Opinions vary widely. The arguments for and against which axle the new tyres should go on have merit and, depending on the vehicle and the driver, it can even be a good decision to fit them against the general consensus.

However, when it comes to a general recommendation, the usual advice from manufacturers, workshops and safe-driving specialists on where to fit new tyres is clear: on the rear axle.

Why are the new tyres fitted to the rear axle?

And, although cars may have front-, rear- or all-wheel drive, the reasoning rests on the fact that steering falls entirely, or in large part if the car has four-wheel steering, on the front axle.

It must be understood that the link between the road surface and the car is the tyres. They are responsible for transferring the engine’s work into grip on the road and, therefore, for the car’s movement.

Having two tyres more worn than the others, or, conversely, driving with two new tyres and two used ones, creates an imbalance in the car’s grip.

The effect of fitting two new tyres for an emergency manoeuvre

That is why, when deciding where the new tyres go, one must understand that the need for balance during an evasive manoeuvre will be decisive for achieving the best result, regardless of which axle or axles are responsible for transmitting the engine’s work to the wheels.

When performing an evasive manoeuvre, the steering axle is responsible for moving the car towards the point the driver has chosen. If the new tyres are fitted to the front axle, the greater grip of the front end will give it more traction than the rear, causing the rear to lose control and, through inertia, go out of control. This would again force a counter-steer once the first evasive manoeuvre has been made, until the trajectory is controlled.

Conversely, if the approach to where the new tyres go favours the rear axle, the front would have less grip due to the wear on its tyres. As a general rule, when an obstacle or dangerous situation is encountered, the driver presses the brake pedal. This causes the car’s inertia and the forces of that deceleration to fall abruptly onto the front axle. At this moment, weight and grip shift to the front of the car. At the same time, the lightness the rear acquires, together with the greater grip of the new tyres, will support the trajectory begun by the evasive movement of the rear wheels.

Oversteer caused

This risky situation would be similar in the case of aquaplaning, driving over a patch of ice or other slippery surfaces, as well as oversteer.

In addition, one of the reasons for considering where the new tyres go may be the renewal and achievement of a new MOT sticker. It should be noted that driving on worn tyres can be a problem, since the check of the condition of the tyres at the new MOT is one of the essential points of the new technical inspection.

Is it better to change tyres two at a time or all four at once?

That is why one of Top10Motor’s car maintenance tips is to change, wherever possible, all four tyres simultaneously.

At the same time, to keep the wheels evenly balanced, especially when changing all four tyres at once, it is advisable to routinely rotate the positions of the tyre pairs, from the front axle to the rear and vice versa. In this way the wear is shared and the useful life of all four tyres is periodically balanced.