Tire Buying Guide: Types & Tactics

Hello,

Whenever the topic of buying new tires comes up, I always find myself thinking about our spare tires.
Both cars (Ibiza 6L and Polo 9N) have full-size spare wheels in the trunk, and were originally equipped with tires of an older design (without directional tread or different inner and outer profiles).
It seems like this particular type of tire is slowly disappearing.
The spare tire for the Polo has been included in the annual tire changeover with summer tires, so currently, the (over 7 years old) factory-installed tire with the most remaining tread is in the trunk (the other 4 will soon be replaced with new winter tires).
We shouldn't expect flat tires to only occur on the side of the vehicle where the directional spare tire is supposed to fit, not until the current spare tire is disposed of.

With the upcoming purchase of winter tires for the Polo, another set of tires with directional tread will be added to the collection, and the Ibiza already has summer and winter tires of the same type.
The like-new spare wheel for the Ibiza was probably never used because it's mounted on a 16-inch steel rim, while the car originally came with 17-inch alloy wheels from the factory.
Since the tire for the IBI spare wheel is no longer being produced, I can't use it effectively with similarly sized SR tires on my steel rims.
So, what should one do with something like that, which is about 5.5 years old? Should it be left indefinitely as a spare tire in the trunk? Or should it eventually be discarded unused and replaced with something new (i.e., with different inner and outer profiles instead of directional tread), even if a matching set of tires isn't purchased?

What kind of tires do you put on the spare wheel when it's not a mini spare, and do your favorite tires always have a directional tread pattern?

In a real emergency, a spare tire will get me home. Otherwise, it wouldn't matter to me if the spare tire is mounted in the wrong direction, or if a spare tire with summer tires makes me mobile again in the winter.

If you look closely and notice how many vehicles manage to get through the winter with tires mounted in the wrong direction, without overturning or skidding off the road in the first turn, then you can actually relax and not worry too much.

Tires must be of the same type and size to be used as a set. Legally, they do not have to have the same tread pattern or be from the same manufacturer. An extreme example from my circle of friends is a 1993 Renault Twingo, which is running with four different sets of summer tires.

In vehicles with overly sensitive ESP systems (i.e., extremely finicky wheel speed sensors), tires with significantly different rolling circumferences (e.g., heavily unevenly worn tread) can already lead to error messages. I know of a Kia Ceed (current model!) that even triggered the ESP system to brake very strongly when the spare tire was mounted, causing it to intervene massively in the driving process in every curve. Apart from the non-removable error message ("Tire damage!"), which simultaneously blocks and renders the onboard computer and radio display unusable, it caused the rear brakes to overheat constantly. Welcome to the new world!

Hutfahrer wrote:

It wouldn't really matter to me during my journey whether the spare tire is mounted in the wrong direction or whether a spare tire with summer tires would make me mobile again in the winter.

Of course, you can see it that way.
However, if an incorrectly sized spare tire is mounted on the front and causes the vehicle to get stuck on a hill, or if the car loses traction and skids during (emergency) braking on snow, contributing to an accident, I don't believe that the usual shared responsibility due to the incorrectly sized tire will simply be dismissed because of a tire failure that occurred shortly before.

Quote:

If you look closely and notice how many vehicles manage to get through the winter with tires mounted in the wrong direction, without overturning or skidding off in the first turn, then you can actually relax and take it easy.

That's right. But if vehicles with incorrectly mounted tires are involved in an accident -> see above

Knowing that the spare tire on the front axle might not be optimal, I don't want to participate in any races.

Hutfahrer wrote:

Knowing that the spare tire on the front axle might not be optimal, I don't want to participate in any races...

Neither do I.
However, even if there's an accident, and the driver of the car with the spare tire bears no fault due to driving errors, the apportionment of blame is still, as far as I know, based on the technical safety features of the vehicles involved.
If the driver of the brand-new, winter-tire-equipped car was solely responsible for all the behavioral issues leading to the accident, the other party involved might only be held significantly liable due to the tire failure that occurred shortly before (and therefore, having an SR and 3 good winter tires on the car)...?

So, in the event of a flat tire, should you immediately call a tow truck, have the vehicle towed, and only resume driving with a completely new set of tires? Because a new tire, even when part of a set that otherwise has used tires, wouldn't necessarily achieve the optimal performance?

The idea that someone using a spare tire could be significantly liable for an accident caused by another party would imply that they were driving a vehicle that was no longer roadworthy, and their insurance company would likely refuse to cover any damages (e.g., comprehensive insurance claim) in such a case. According to a mechanic friend, the handling of a car with a spare tire is considered as part of the vehicle's approval process (ABE) when it is delivered with the spare tire or if the spare tire is offered as an optional accessory. Any limitations on use (e.g., a speed restriction with a spare tire installed) would result from this. However, he believes that it is an overstatement to conclude that a car driven home in such an emergency situation is practically no longer roadworthy. If that were the case, the spare tire would even be classified as prohibited equipment and should not be installed or used.


Okay, here's the translation:

"Slightly off-topic: 13 years ago, I drove home from a car meet in Mecklenburg on four spare tires. The night before, all four wheels (Mattig chrome steel rims, with ATU wheel locks) had been stolen from my car. I found four attendees who lent me their spare tires, or even gave them to me. The theft was reported to the police, and the officers had no problem with me driving home on four spare tires, as long as I took the necessary precautions."

Hutfahrer wrote:

The fact that someone using a spare tire on a vehicle should bear significant responsibility for an accident caused by another party would, conversely, mean that they were participating in road traffic with a vehicle that was no longer roadworthy, and their insurance company would even be liable to refuse coverage in the event of damage (e.g., comprehensive insurance claim). According to a friendly automotive mechanic, the handling of a car with a spare tire is tested as part of the vehicle's approval (ABE) if it is delivered with the spare tire or if it is available as an optional accessory.

Let's consider, instead of the insignificant spare tire, the following example of an accident on a winter road with icy conditions:
A car (A) equipped with 4 new winter tires cuts in front of another car (B) which is equipped with 3 winter tires with sufficient tread and 1 summer tire. Car B, despite immediately applying full brakes, is unable to stop in time -> CRASH -> 5000€ in property damage, no personal injuries.

Background 1:
The owner of car B had a flat tire 10 minutes prior and had to install the factory-supplied spare tire (of the same size). The flat tire is still in the trunk.

Background 2:
The owner of car B had contacted all the tire dealers in the area, but only received 3 winter tires that were suitable for his car. As a result, he has been driving with only 1 winter tire (of the same type and size as the winter tires) for several months. There is another spare tire of the same type in the trunk.

Background Story 3:
The owner of car B only had enough money for 3 winter tires, so he has been driving with only 1 summer tire (of the same type and size as the winter tires) for months. There is another summer tire in the trunk as a spare.



Modified accident sequence on a Sunday afternoon:
Car B was traveling with 3 spare tires and the optional factory-installed spare tire after experiencing a flat tire. The owner's manual for car model B recommends replacing the damaged tire as soon as possible.
According to an expert opinion commissioned by driver A, the braking distance of car B with 4 WR (presumably referring to a specific tire type or condition) would have been significantly shorter, which would have prevented the accident from occurring.

Background 1:
The tire blowout happened 4 weeks ago. The defective winter tire could have easily been replaced in time before the accident due to the market conditions, but the owner didn't have the time to do so due to constant work and family-related stress.


Background 2:
The flat tire occurred two days prior, on Friday afternoon. The driver had a work appointment that afternoon and was therefore unable to take care of getting a new winter tire.




Do you think that insurance companies or courts would determine the apportionment of blame in cases with identical objective accident scenarios based on the parties' prior history?

@Ulf: You could also be killed by a piece of debris from the Rosat... one thing is certain: Life ends fatally.
Personally, I prefer a full-size summer tire as a "spare tire" rather than a mini-spare or a can of sealant. Therefore, it's smart to have summer and winter tires in the same dimensions.

But who would actually drive around for months with the wrong tires?

Best regards, Rainer.

Spray cans are never used by me. This decision was made after a local tire dealer stated that "repaired" tires and rims should be immediately disposed of. He explained that tires that have been patched with repair sprays could only be removed from the rim by chiseling. Furthermore, he said that the repair material is so aggressive that it would damage both alloy and steel rims, leading to corrosion, and that he could not guarantee the permanent seal or operational safety. He would remove such a wheel and either have the customer dispose of it or charge them for the disposal. The customer would have to separate the rim and tire for this purpose.

Considering the statistically low probability of a tire puncture, carrying a full-size spare tire, which I must assume retains its properties for at least one weather season and therefore differs from the defective and removed tire, is practically pointless. Space-saving and lighter alternatives are run-flat tires, which can also serve as a way to get you home in an emergency. This was a factory-installed option in my vehicle and is therefore approved by the manufacturer for this vehicle. As long as I adhere to the usage condition of "maximum 80 km/h," I can continue to consider and operate this vehicle as suitable for road use.

The spare tire, including the storage basket attached to the vehicle's undercarriage, is part of the manufacturer's approval documentation. To keep it in working order, I regularly check the tire pressure (unfortunately, I have to crouch behind the vehicle to reach the valve) and recently re-lubricated the crank mechanism for releasing air. So, it should function in an emergency! However, the car jack, which is located in the spare tire and therefore completely covered in dirt, can be stored inside the vehicle. Otherwise, it would just rust down there.

Hutfahrer wrote:

Considering the statistically very low probability of a tire puncture, carrying a full-size spare tire, which I must assume at least during one weather season will not have the same characteristics as the defective and removed tire, is practically pointless.

. . . and space-saving and lighter alternatives are run-flat tires, which can also serve as a way to get you home in an emergency. They also never match the summer or winter tires because you always know what you have.

Ibiza-BA wrote:

If you have to use them in an exceptional case, you are entering legally precarious territory, as is hinted at in the various vehicle operating manuals. Example Ibiza 6L:

The spare tire is only intended for emergency use until you reach a workshop. Therefore, replace it with a normal tire as soon as possible. But what does "as soon as possible" mean?
Must a driver, for example, who is returning home on vacation and experiences a tire blowout on Sunday afternoon in Oberstdorf, stop at the next tire service, because driving 1100 km back home with a maximum allowed speed of 60 or 80 km/h while using a spare tire is too risky? Or is he allowed to drive home, as the owner's manual does not require a stop at the nearest} workshop?

While driving with a spare tire might be covered by vehicle regulations, in the event of an accident involving a spare tire, I believe you enter a situation where the apportionment of blame becomes a complete gamble.

Because if even a driver who is completely innocent in the eyes of the law is judged based on the theoretical ideal of driving behavior, and any deviation from this ideal results in a share of blame in the distribution of damages, then it is my opinion that an innocent driver with a permissible spare tire in the car (where the vehicle registration document already warns "Caution!!") will be in a worse position than one with a complete set of matching tires. After all, an ideal driver would naturally have a full-size spare tire on board that perfectly matches the other tires. And if not, the ideal driver would actually have the car towed after a tire puncture.

Conversely, simply using a full-size replacement wheel with the incorrect direction of rotation would likely imply a certain degree of responsibility.

dieselschrauber wrote:

@Ulf: You can also be killed by a piece of scrap from the Rosat... one thing is certain: Life ends fatally. Personally, I prefer a full-size summer tire as a "spare tire" rather than a mini-spare or a can of tire sealant. Therefore, it's smart to have summer and winter tires in the same dimensions. But who would actually drive around for months with the wrong tires? Best regards, Rainer

I see it that way too!

"Coram iudice et in alto mari sumus in manu Dei."
"Before the court and on the high seas, we are in God's hands."

This Roman legal wisdom still largely holds true today. Valid law is one thing, getting what is rightfully yours is another. And as long as courts can issue rulings that clearly contradict existing law, and these rulings cannot be successfully challenged even through multiple appeals, I no longer categorically exclude the possibility that a driver could be held responsible for something they neither caused in any way nor could have prevented through their own actions.


To put it bluntly: A vehicle, which is typically 3 years old, receives new tires. The tire model that was originally mounted has worn out and has been replaced by the manufacturer with a newer model. While this newer model is available in the required dimensions, it neither matches the original model in terms of rubber compound nor tread pattern. If the car owner now chooses the newer model or even a completely different tire, could they be held partially responsible in an accident, even though they were not the cause? Let's take this even further! Tire tests show generally quite variable results. Could a driver be held partially responsible in an accident if they happen to be using a tire with a longer braking distance than the one identified as having the shortest braking distance in the test? And which test is now decisive?

Hutfahrer wrote:

Does the car owner now choose the successor model or even a completely different tire - will they, as a non-offender in an accident, be held partially liable? Does a driver bear partial responsibility in an accident if, by chance, the tire with the shortest braking distance determined in a test is not the one installed on that particular wheel of their vehicle? And which test is now decisive?

As far as I know, fortunately, no one (publicly) has thought of this yet when making decisions about apportioning blame.

However, the fact that decisions are already being made based on tread depth and tire types (summer/winter) led me to think in the direction of this thread.

We have experienced manufacturer-imposed tire restrictions in the past. This was overturned at the time thanks to EU legislation. Previously, vehicle owners regularly faced the problem of obtaining a certificate of conformity from the vehicle manufacturer when the required tire model was no longer available or if they wanted to install something different.

Despite this, she continued to be used with motorcycles, trailers, tour buses, and trucks – even though the tire regulations had long been outdated. However, manufacturers insisted that their vehicles could only achieve the desired characteristics when used exclusively with the prescribed tires. As a last resort, trailer manufacturers even attempted to link the "Tempo 100" approval (allowing a speed of 100 km/h) to the use of a specific tire model.


However, they still have one card up their sleeve: If the intended EU draft law to tighten emission standards becomes a reality, it could prove costly for vehicle owners. It stipulates that measures for reducing fuel consumption and noise, which have been achieved through the vehicle's design, must not be undermined by accessories or modifications. Austria is already implementing this proactively, making it difficult or almost impossible to install wider wheel/tire combinations, different exhaust systems, or body parts. At this point, manufacturers could again resort to tying tires, claiming that consumption or noise levels would no longer be met without them. In the case of spare parts, the end consumer would then be reliant on OEM or certified replacement parts. The latter would have to demonstrate, as part of an inspection, that their properties do not, in any way, worsen the vehicle's fuel consumption or noise levels. Since the draft law also requires long-term stability, spare parts will likely no longer be available as cheaply, and the installation of non-certified spare parts would be illegal.

Ulf, the spare tire is only meant for dealing with emergencies, not for driving long distances. It should only be used to get you to the nearest repair shop. Anything beyond that is generally not allowed.


Buy an all-wheel drive vehicle, and you'll get rid of that spare tire right away!
Why?
Because even a tire with 2mm more tread can ruin your all-wheel drive system. Especially viscous couplings or similar designs don't last long under those conditions.
My forester doesn't have a spare tire (besides, the gas tank is located there). If I have a flat tire, the vehicle will be towed away as quickly as possible... without any discussion.