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Oh, ok. Performance tires on every application.
That is not what I wrote. Go back to the previous post and read again.
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That's a novel idea that I have never encountered before. Do you want to break the news to the OP's mom that she not only should get tires that wear out 2x-3x as fast, but she'll need another set of tires and rims just for winter. I'd pay to see that.
Actually, that is not a novel idea; it is the
law in much of the world, where the mounting of "all-season" tires is illegal, for the very reason of their compromised wet braking. "All-season" tires are very much a North American phenomenon where, unlike much of the rest of the world, most jurisdictions do not even have mandatory vehicle safety inspections, nothing to ensure that the car coming towards you at 65 mph has even working brakes.
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You also failed to address the temp issue. Are you sure that at +30f wet slush the "performance" tire really has more traction? Are you familliar with compounding techniques for colder temps?
Yes, to the latter question; a
usual yes to the former question. There is a reason why real winter tires generally have low wear ratings: compounds that stay flexible at low temperatures generally are relatively soft and wear quickly. There is a reason why all-season tires generally have high wear ratings: all-season tires are specifically marketed to purchasers who think they are getting something for nothing in getting an "extra" season thrown in for free with an all-season tire, people who tend to be the same people who think that there is no trade-off in having a tire that wears better, that a better-wearing tire is
for that reason a better tire than a tire that wears faster. In fact, there is no secret in how to make a tire wear well, and very hard, very unsticky, tread compounds are a major part of the formula. Hard rubber does not have as high a coefficient of friction with the pavement as soft rubber does.
With very few exceptions, a three-season tire with a grippy tread compound will behave better at above-freezing temperatures in the 30s and 40s (F.) than an all-season tire with a tread compound hardened for long wear. The best performing tires of all under such conditions, of course, are the Finnish Nokian three-season tires (NR-V, NR-Z, etc.) optimized specifically for that temperature range. Nokian, however, does not recommend those tires for snow; for snow, Nokian recommends real winter tires.
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Now, think...the original poster is from Canada. Get the picture?
Yes; in winter, she needs real winter tires, not pseudo-all-season tires.
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Also, can you back up the "coupla car lengths" claim? Let's get a grip, shall we?
Yes, I can. The most accessible tests published on-line are at TireRack dot com. You have to be careful making comparisons
across test groupings at Tire Rack, because each set of tests is conducted outside under ambient conditions that are not replicated in other sets of tests, and the personnel conducting the tests varies from grouping to grouping; but the tests yield fairly reliable data
within each test grouping. Unfortunately, the size of Tire Rack's test facility limits brake testing to 50 mph. However, even with that restriction, Tire Rack has performed several comparison tests of sets of tires in which one set of tires under test were all-season tires. Looking just at the wet braking results, here is an incomplete sampling:
2003 August 1: three sets of "summer" tires, one set of "all season." All season finished fourth of four.
2004 May 28: three sets of "summer" tires, one set of "all season." All season finished fourth of four.
2004 September 22: three sets of "summer" tires, one set of "all season." All season finished fourth of four.
2004 October 14: three sets of "summer" tires, one set of "all season." All season finished fourth of four.
2004 November 12: three sets of "summer" tires, one "all season." All season finished fourth of four.
2005 April 15: three sets of "summer" tires, one set of "all season." All season finished fourth of four.
2005 May 13: four sets of "all season" tires. Interesting result is that the same tire (Goodyear RS-A) that had finished dead last in several of the above tests against "summer" tires finished first of four -- by a comfortable margin -- against fellow "all season" tires.
2005 May 27: three sets of "summer" tires, one set of "all season." All season finished fourth of four.
Do you detect a pattern?
Now, I have a question for you: do you know of any controlled test that shows any all-season tire having wet braking performance superior -- or even equal -- to any three-season tire? I should be interested to see it.
