In recent weeks we have had days of heavy snowfall for a large part the Iberian Peninsula; especially in these last few days and, let us remember, at the end of last Christmas, during the Three Kings Day festivity. A lots of drivers were trapped on the roads, either due to lack of information or due to misconduct by those who ventured with their vehicles in the face of a storm without taking the necessary measures.
We recently attended a campaign event “Change your habits, change your tires” promoted by the Tire Manufacturers Commission. The place chosen for the tire tests, comparing winter wheels with conventional tires, was the Xanadú shopping center in Madrid, carrying out the tests both on a slippery surface track and in the SnowZone itself from the shopping center; that is, in a snow track. That said, we are going to tell you our feelings.
After a press conference in which José Luis Rodríguez, director of the National Rubber Industry Consortium, represented us the behavioral advantages and differences of conventional tires, allseason and winter wheels, it was time to get behind the wheel. Our shift would start at sliding track located in the parking lot of the aforementioned shopping center, where identical Volkswagen Golfs were waiting for us except for having winter tires in some cases and "normal" wheels in others.
Winter tires VS conventional tires
We would first do a strong acceleration, of about 15 meters to check the traction of the cars with the different types of tires. In this test, the front-wheel drive cars had the same engine and double-clutch gearbox, leaving the electronic controls activated. To compare as evenly as possible, we put the transmission in sport mode and went full throttle without hitting the kick-down button.
Despite the fact that the speed difference with which we left the slippery area was not very great, approximately 28 km/h with winter tires and 25 km/h with conventional ones, the sensations were very different. With the winter tires electronic aids of traction came into operation, but very punctually and hardly noticing them; while with the “summer” wheels practically did not stop acting, clearly noticeable by the noises they generate and, of course, by the warning light on the instrument panel.
From there we went to braking zone, performing an emergency braking at 50 km/h, also on sliding surface. The difference between both vehicles -equipped with tires of different types, at the same speed and braking at the same point- was between three and four meters. Distance that would rise notably as we increased the speed at the starting point of the braking
4 meters may not seem like much of a difference, but keep in mind that four meters is what measures a segment B car, type Renault Clio. So we can go from having a slight scare to having to replace a good part of our front in the event of a rear-end collision. In case of being run over, the upset would be much greater. In addition, if we try to correct the trajectory in full braking, the winter tire better obeys our commands on the steering wheel.
winter wheels in snow
It was time to re-enter the SnowZone of the Xanadú shopping center. The organization had made short and simple outline ascending and descending with some curves so that, at the controls of a Nissan X-Trail diesel 4×4 and manual gearbox, we could appreciate the grip of the winter wheels. In this case, we would not test normal tires. I honestly don't think we would have been able to complete it.
A first lap with 4×4 traction activated and the all way ascends and traces the curves No problem if we are relatively soft on the gas. In case of sudden acceleration, as is logical, some loss of traction appears and the aids come into action, but we maintain a sense of control at all times. On the descent, we dodge the cone slalom at a prudent speed and without drifting.
We do the second round of the snow route only with front wheel drive, without activating the 4×4 drive. The loss of adhesion of the front end are greater, something that was very expected, but we keep moving forward safely. This time, in the cone slalom descent, we decided to demand a little more and perform powerful braking with the car turning. The ABS kicks in quickly and, of course, the grip is much lower than it would be on dry ground, but even so we surprise for good, guiding correctly.
What are the differences between a winter tire and a "summer" tire?
Many. Naked eye, the drawing of one and the other will make us easily distinguish them. We all know what normal wheels look like; but maybe not all of you have seen winter tires. First of all, the heel height it is somewhat higher for winter wheels, whose objective is to evacuate as much water (or snow or mud). We will also see that some small slots or sipes on the studs, which provide greater grip under acceleration and braking on icy or snowy ground. Lastly, the compounds used and firing formulas are different, the winter tires being noticeably softer.
How is the specific marking of winter wheels?
With the aim of making it even easier to distinguish one from the other, between the acronyms and numbers that appear on the tire profiles, we will be able to see the registration of “Mud and Snow” with the acronym MS, M+S or M&S. In this case, they are homologated winter wheels but have not been tested in winter conditions.
El marking “3PMSF”, with a pictogram showing a mountain with three peaks and a snowflake inside, indicates that this specific tire model has been subjected to specific winter tests and that, in addition, it has passed them according to the ETRTO (European Ture Run Technical Organization) certification method.
When is it advisable to install winter tires?
Keep in mind that all depends on weather and climate in which we move normally. If we live in Tenerife, for example, we can practically rule out its acquisition. However, in most of the peninsula temperatures are very cold for four or five months of the year, with regular snowfall in certain areas and heights above sea level.
According to experts, the winter tire offers better grip on dry asphalt when the ambient temperature, taken as a reference (because we can have very cold asphalt and higher ambient temperature), is 7 degrees Celsius. Needless to say, if it snows, rains or freezes frequently in the geographical area where we move, winter wheels will be a great ally.
In this way, it would be advisable to have two games of tires, some for winter and others for summer; installing the winter ones approximately in the season that goes from November to March, reassembling the summer game for the rest of the season. In any case, this is somewhat indicative, because, as we said, it depends a lot on the areas through which we circulate.
winter tires in summer
Many of you may have the doubt what happens if i use winter tires during the summer. First of all, to say that it is totally legal, so in places where temperatures are not very high in summer, it is even feasible to mount only and exclusively winter tires.
In any case, in most of the peninsula during the summer quite high temperatures are reached. We said earlier that the winter tires provide more grip below 7 degrees compared to conventional wheels. Above those 7 degrees, the grip is somewhat lower and its wear, being softer compounds and having more aggressive studs, is faster. That is why it is recommended to have two sets of tires, to make better use of capabilities and durability of each of them.
Winter wheels only on the drive axle?
You already know that chains are installed only on the drive axle, that is, on the axis that sends the energy of the engine to the asphalt. In the case of winter wheels, it is more advisable to install them on all four wheels. If for any reason we can only install one pair, we will do it on the drive axle, but you will immediately understand why the recommendation of the four winter wheels.
In the case of chains, their use is only necessary on the drive axle because they are reserved for very specific use in which we are interested in a plus of adherence to move forward. Much more is required of winter tires, both in the dry and on low-grip surfaces, so if we only carry these wheels on one axle we will be somewhat unbalanced. In this case, a front-wheel drive car would be more prone to spin, while a rear-wheel drive car would have more understeer behavior.
Do I need chains with winter wheels?
No, do not use chains with winter tires. Winter tires are substitutes for chains and, to tell the truth, they are considerably more practical, comfortable and efficient. The winter chains are only used to advance when the layer of ice or snow is important, having to uninstall them when we touch clean asphalt to avoid damage; while the winter wheels guarantee good grip both in those complicated conditions and with dry ground and very cold asphalt, that is, at all times.
Advantages of winter tires compared to summer tires in the winter season
- Greater traction capacity in practically any situation.
- Reduced risk of aquaplaning.
- Reduced braking distance.
- Possibility of driving on snow with guarantees and without using chains.
Advantages of winter wheels compared to the use of chains
- We can use them on any surface.
- It is safer and much more comfortable as you do not have to stop to mount and dismount it constantly.
- Some chains are not compatible with all types of cars or tires.
- Winter tires can be mounted on both wheel axles, compensating for the behavior of the vehicle. The chains only go on the drivetrain.
