A reader writes:
Always reading your rants and enjoying them. On the subject of tires again, you refer to so-called "All Season Tires" as No Season Tires. What is wrong with those tires in temperatures above 7C?
A writer (ahem - that's me) responds:
All tires are compromises, and with perhaps one exception that a reader mentioned and my tire guru has verified (Nokian WR, which I haven't personally tested) there really isn't any tire with a broad enough range of performance attributes to be truly useful in every weather condition.
All-seasons attempt to give acceptable levels of performance in dry, wet or snow, combined with low tread wear and high fuel economy. This latter point is critical for car makers because they get fined in the US if their cars don't meet fuel consumption standards (Corporate Average Fuel Economy - CAFE - regulations). You wouldn't believe how hard they work for a single mile per gallon, because CAFE is a sales-weighted calculation, and a small plus over hundreds of thousands of vehicles really adds up.
Unfortunately, the things that make a tire last a long time and give good fuel economy also reduce grip, especially in wet weather which is when you need it the most.
Because grip is the single most important characteristic your car can have (nothing else matters if the tires can't communicate what you or the car's other systems are trying to do), I believe you should have proper summer tires, preferably those biased towards wet weather grip if possible, from spring through fall, and proper winter tires in winter.
BTW, don't let the fabulous weather of the past few days fool you into taking those winter tires off too soon. Ol' Man Winter isn't done with us yet - remember this coming Tuesday who told you so.