The flaw of all‑season tires: Just do the math

All-season tires enjoy massive popularity among drivers, owing to their versatility and simplicity of use. They work perfectly in moderate weather conditions, such as those typical in Central Europe. Currently, they strike a fine balance between summer and winter tires, offering an excellent compromise. Independent tests verify that though all-season tires may not be the best choice in extreme conditions—which occur very rarely—they maintain an impressive performance.

The one drawback of all-season tires is often overlooked by many drivers. Given their year-round use, these tires accrue substantial mileage, which subsequently contributes to their continuous wear and tear. When compared to seasonal tires, which enjoy periods of rest (winter tires in the summer and summer tires in the winter), all-season tires rack up miles non-stop, which affects their life span.

Consider this scenario: a driver travels roughly 7500 miles a year, which averages out to about 620 miles a month. In this case, summer tires would cover an annual distance of approximately 4350-4980 miles, while winter tires would cover a range of 2485-3105 miles. Assuming the average life span of any tire type is 18640 miles, we can estimate their durability.

By the end of three years, seasonal tires (summer ones, in particular) would have covered distances ranging from 13030-14915 miles, while the winter ones would have ranged from 7450-9310 miles. Both sets would likely still be in good shape. Summer tires could even extend into a fourth year of usage, while winter tires could last for two more seasons.

Conversely, in the same three-year period, all-season tires would have covered a distance of around 22370 miles, prematurely signalling the necessity for replacement. Just after two years and approximately 14915 miles, all-season tires show comparable wear to summer tires and considerably more wear than winter tires. In practice, they might scrape through to the end of the summer after two years of use, but they would not be well suited for winter use. Added to this, all-season tires tend to wear marginally quicker in the summer due to their softer compound.

A realistic calculation shows that after three years of use and about 12300 miles, all-season tires would have barely 0.16 inches of tread depth remaining. If these were purchased just before the 2020/2021 winter season, they would be ill-suited for the winter of 2023/2024, although they could still eke out the entire following summer. With gentle use and an assumed annual mileage of around 3105 miles, these tires could last three winters and three summers. If the annual mileage were to rise to around 7500 miles, though, replacement would be needed just after two years.

Interestingly, the wear on these tires appears to be quite uniform, despite a lack of rotation. However, this may not always be the case. In many cars, the front tires are bound to wear out faster than the rear ones when not rotated regularly. Thus, with visible uneven wear on the axles, front tires could deteriorate even sooner.

To conclude, all-season tires do not guarantee absolute peace of mind. Users wouldn't fret over the question of "when to replace tires" or hunt for a tire shop and pay for tire replacement. However, it's crucial to check the tread thickness, preferably before winter, considering the upcoming season's demands.

Apart from this, consistent rotation of tires once a year is wise. Unfortunately, this also implies the need for more frequent tire replacements. Saving money isn't just about buying one set of tires as opposed to two—it also involves minimizing expenditure on tire replacements, unlike those who use one set of rims and two sets of tires.