Perhaps in your experience as a driver you have wondered whether your pair of tyres that are in better condition, should be mounted on the front or the rear axle of your car. If so, you're not the only one! We've received a lot of questions about this. Therefore, we have prepared a list of tests for our readers.

The car's axle

Back when tube tyres were used, it was believed that better tyres should be fitted on the front axle to protect the car from being pulled of the road in the event of a puncture. However, current tubeless tyres are safer and in the event of a puncture, the air will escape at a much slower rate than from old tyres.

When the market got dominated by rear-wheel drive cars the opinion changed and the better pair of tyres was supposed to be mounted on the drive axle, in this case the rear axle. This is how the theory that the better tyres should always be mounted on the rear axle was developed. 

Over the years, this changed, because nowadays most cars are front-drive. 

Four separate organisations have conducted independent tests to show which axle it's more sensible to fit the better tyres on. 

Properly fitted tyres are the key to safe driving in difficult conditions.

Which axle should the better tyres be mounted on? TCS test

The experts took an ideal situation as a baseline: four new tyres.

The first and second combinations tested tyres of the same brand, from the same period of production, that differed in tread depth by no more than 1.5 mm. The trials simulated the situation of buying two tyres, and in a year's time buying two identical tyres in a set. In the test, the better tyres were first fitted on the rear axle and then on the front axle.

In the third and fourth combination, tyres of different brands, differing in production date and tread depth by no more than 3 mm, were tested. As in the first two combinations, the better tyres were first fitted on the rear axle and then on the front axle.

The following performances were compared during the test:

  • aquaplaning,

  • ABS wet braking,

  • circle driving on wet roads,

  • wet handling without ESP,

  • wet handling with ESP,

  • changing lanes on wet roads without ESP,

  • ABS braking on dry surfaces.

Combination 1 – Better pair of tyres on the rear axle

When you mount better tyres (with more tread depth) on the rear, it will slightly negatively affect:

  • resistance to aquaplaning,

  • braking and wet steering in cars without ESP (in a car equipped with such a system, the difference in steering will not be felt too much).

Nevertheless, better tyres mounted on the back will not affect your car's performance when suddenly changing lanes on wet roads, e.g. when avoiding an obstacle.

And this is important in terms of safety. Loss of stability (back-casting) in case of sudden turning is particularly dangerous.

In the event of losing stability of the front axle, it is much easier to stabilize the car than if you lose the grip of the rear axle, which is much more problematic.

Combination 2 – Less worn out tyres on the front axle

Surprisingly, if you fit the better tyres on the front axle, braking and handling on wet roads will also deteriorate slightly. In addition, the car will become more unstable in the event of sudden lane changes on wet roads, as mentioned when discussing combination 1.

The car, however, will be a little less susceptible to aquaplaning.

CONCLUSION:

Each combination of two similar pairs of tyres has its own advantages and disadvantages. Fitting better tyres on the rear axle is safer especially in emergency situations where you need to avoid an obstacle that suddenly appears on the road. Then the rear axle is more "loaded" and less prone to loss of grip, and that's where it's better to keep your tyres in better condition.

Combination 3 – Much better tyres on the rear axle

In this case, imagine that you have two completely different pairs of tyres (model, production time, tread depth). If you mount the better ones on the rear axle, braking on wet roads with an ABS system will deteriorate significantly. Taking corners on wet roads without an ESP will worsen to a medium degree. The following will deteriorate less:

  • sideways aquaplaning,

  • wet handling with ESP,

  • ABS braking on dry road surfaces.

Combination 4 –  Best tyres in the front

If you mount your tyres that are in better condition at the front and your tyres that are in worse condition on the rear axle, three of the following results will worsen significantly:

  • wet handling without ESP,

  • wet handling with ESP,

  • changing lanes on wet roads without ESP.

Such a solution also makes cornering worse on wet surfaces.

On the other hand, braking on dry and wet surfaces as well as aquaplaning resistance don't worsen.

CONCLUSION:

There is no ideal solution for tyres that differ significantly in performance either, but just like for combinations 1 and 2, it is advisable to fit better tyres on the rear axle. Front-mounted tyres in better condition significantly reduce the stability and handling in emergency situations and in wet weather. To reduce the risk of skidding when maneuvering suddenly, it is recommended that the better tyres should be fitted to the rear axle despite the deterioration in braking distance.

NOTE:

Also remember to regularly rotate tyres between the axles every 10,000 km, to keep all tyres in a similar condition and avoid uneven tyre wear (only when the starting point was 4 identical tyres).

Results in terms of individual performance:

Aquaplaning – BEST TYRES ON THE FRONT AXLE

Wet braking with ABS – BEST TYRES ON THE FRONT AXLE 

Cornering on a wet surface – BEST TYRES ON THE FRONT AXLE 

Wet steering without ESP – BEST TYRES ON THE REAR AXLE 

Wet handling with ESP – BEST TYRES ON THE REAR AXLE with large tyre difference / BEST TYRES ON THE FRONT AXLE with small tyre difference

Changing lanes on wet roads without ESP – BEST TYRES ON THE REAR AXLE 

ABS dry braking – BETTER TYRES ON THE FRONT AXLE  (the differences in the results were not big)

Michelin test

The test was carried out using a front-wheel drive, rear-wheel drive and four-wheel drive car. According to the results below, the driver - relying on their skills and drive of their vehicle - should make a rational decision about which axle requires better treaded tyres. Thus, according to Michelinevery option has its advantages and disadvantages. Details can be found in the tables below:

 

Front drive vehicles

Better tyres at the front of the vehicle

Better tyres at the rear of the vehicle 

Advantages of fitting better tyres on the front

Disadvantages of fitting better tyres on the front

Advantages of fitting better tyres on the back

Disadvantages of fitting better tyres on the back

  • Optimal grip when accelerating on  wet surfaces.
  • Short braking distance on snow-covered and wet roads.
  • Good grip on dry and wet surfaces.
  • High aquaplaning resistance when driving straight.
  • Worse braking on wet bends.
  • Low resistance to aquaplaning while turning and cornering.
  • More skidding on wet roads.
  • poorer braking on sharp corners.
  • High aquaplaning resistance when cornering fast
  • More skidding of the car on a wet.
  • Short braking distance on wet roads on bends.
  • Low grip on dry and wet surfaces.
  • Poorer braking  on snow-covered and wet roads.
  • Less grip when accelerating on dry and wet surfaces.
  • More “fishtailing” on dry roads.
  • Less comfort while turning corners.
  • Worse acceleration on bends.
  • Lower aquaplaning resistance when driving straight.
  • More skidding on dry roads.

Rear-wheel drive cars 

Better tyres on the front of the vehicle

Better tyres at the back of the vehicle

Advantages of fitting better tyres on the front

Disadvantages of fitting better tyres on the front

Advantages of fitting better tyres on the back

Disadvantages of fitting better tyres on the back

  • Short braking distance on snow-covered and wet roads.
  • Safe and comfortable driving on long dry bends.
  • Reduced skidding while cornering on dry roads.
  • Less grip when accelerating on an ice- and snow-covered road.
  • Longer braking distance when taking corners on wet and dry roads.
  • Lower aquaplaning resistance when driving straight  and cornering.
  • More chances of skidding on wet corners.
  • Good acceleration on corners on snow-covered roads.
  • Short braking distance on bends on wet and dry roads.
  • Resistant to aquaplaning when driving straight, on bends and corners.
  • Less skidding on bends on wet roads.
  • Lower braking stability on ice- and snow-covered roads.
  • Less grip when taking long corners on dry roads.
  • Skidding while driving on a dry road.

Cars with 4x4 drive

Better tyres on the front of the vehicle

Better tyres on the back of the vehicle

Advantages of fitting better tyres on the front

Disadvantages of fitting better tyres on the front

Advantages of fitting better tyres on the back

Disadvantages of fitting better tyres on the back

  • Short braking distance on snow-covered and wet roads.
  • Safe and comfortable handling on long dry corners.
  • Less skidding on dry bends.
  • Less grip when accelerating on an ice- and snow-covered road.
  • Worse braking on dry corners.
  • Low aquaplaning resistance when driving straight and cornering.
  • Skidding on wet corners.
  • Good acceleration while cornering on snow-covered roads.
  • Short braking distance when turning corners on wet and dry roads.
  • High resistance to aquaplaning when driving straight and on bends.
  • Less skidding when turning on wet roads.
  • Less stability when braking on ice and snow-covered roads.
  • Less grip when taking long turns on dry roads.
  • Skidding on dry surfaces.

ADAC test

The test drives took place on a track - on a slippery road, on a dry surface and on a wet surface. The subject of the test was to compare the performance of a front wheel drive car in a variety of tyre configurations – with almost worn out tyres on the rear axle and new tyres on the front axle, with new tyres on the rear axle and almost worn out tyres on the front, and with new tyres on both axles. All tests were carried out first with track control (ESC or DTC, VDC, ESP, etc.) and traction control (ASR, TC, etc.) systems activated and then deactivated.

On a slippery, partially wet track, the most successful cars were those with four new tyres. In the case of cars equipped with new tyres on the front axle, the cars accelerated equally quickly, but when trying to turn a corner at the same speed, they easily skidded of the track. These cars were also unstable, unpredictable and drove straight with the wheels twisted (all this took place at a speed of up to 70 km/h). In order to complete the pre-determined route, the driver had to reduce their speed by about 10-15 km/h compared to a car equipped with 4 new tyres.

Vehicles with new tyres on the rear axle and more worn out tyres on the front axle performed much better. Starting and accelerating the car was more troublesome and it became possible to lose grip during sudden acceleration, but the rear remained stable and the car did not "float" to the sides. The driving speed proved to be about 5-10 km/h higher than in the case of a car with almost worn out tyres on the rear axle and new tyres on the front axle. In some cases, the results were similar to those achieved with new tyres on both axles. This depended on whether the front tyres were already starting to lose grip or whether the grooves in the front tyres were still able to drain the water.

Significantly greater differences were found when driving around corners and with large changes in accelerator pedal pressure and brake application when entering corners. The speed differences reached 20 km/h and in most cases were about 30% in favour of a solution with better tyres on the rear axle, regardless of the level of technical training of the driver. These differences became greater as the speed and dynamics of braking and accelerating increased.

Driving with better tyres on the rear axle in a front drive car has more advantages. Starting and accelerating difficulties are an immediate signal to the driver that the ground is slippery and special care must be taken. Reverse tyre mounting works the other way around, giving the driver a false sense of security. 

It is also worth mentioning that fitting a better pair of tyres on the back of a front-drive car, wears the tread more quickly on the tyres on the front axle. In addition, if the profile on the front tyres is heavily used, then understeer may occur. In order to reduce the difference in tread wear, the wheels can be moved between the axles provided that the difference is at least 1 mm. If the differences in the depth of the grooves are greater (2-3 mm), replace one of the pairs of tyres beforehand.

The choice of axle where you mount your better tyres impacts the risk of aquaplaning.

ÖAMTC test

The conclusions of the Austrian ÖAMTC (Österreichische Automobil Motorrad und Touring Club) research are as follows:

  • Worse tyres in the rear are associated with the risk of slipping and dangerous side impacts. This also applies to front wheel drive vehicles.

  • Worse front tyres significantly increase the braking distance.

  • With tyres that vary greatly in terms of wear and tear, the risk of accidents increases.

  • The better tyres mounted on the front axle provide shorter braking distances and greater aquaplaning protection.

  • Better rear-mounted tyres increase stability when suddenly changing lanes and improve cornering, especially in wet conditions.

If you have tyres with a small difference in tread thickness (1 mm), the difference in comfort is not noticeable and the ESP system will do well in improving the track control.

ÖAMTC recommends that in the event of significant tyre wear, a new tyre set should be purchased. If you only buy two tyres, Austrian specialists recommend fitting the better tyres on the rear axle of your vehicle.

In our opinion

An unexpected and strong rear-end skid during braking on slippery roads and corners is a very dangerous situation to deal with, because you can quickly lose control of your car. You can also reduce the steering ability of your car, which can be improved by reducing your speed or braking. This is why car and tyre manufacturers often recommend that less worn or new tyres should always be fitted on the rear axle - regardless of whether the car is fitted with rear-wheel drive or front-wheel drive.

Aquaplaning can be felt when the wheels on the front axle of the vehicle lose contact with the surface. It cannot be felt when the rear wheels lose contact with the road surface. This is why it is dangerous to fit tyres with a smaller tread on the rear axle.

Another concern for drivers may be that they are more likely to burst a tyre that has a lower tread depth and is on the front axle. The tyres are reinforced in the tread area by strong steel belt layers. When driving into a hole or running over something at high speed, it can be enough to burst the tyre.

It is also worth remembering that you should change all your tyres when all four are heavily worn out. It's not recommended to fit two winter tyres on one axle only, due to the imbalance of the car's equilibrium. This can also lead to a loss of grip and dangerous road accidents.

Please note that under certain conditions, better tyres can be fitted on the front axle, but these are not common situations. If you don't have the time to test and analyse your tyres thoroughly, then whatever the drive system of your car, a better, safer and more versatile solution will be to fit the better tyres on the rear axle.