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A reasonable choice Posted by Ari [Email]  (#2847) [Profile/Gallery]
(more from Ari) on Thu, 28 Aug 2008 20:51:48
In Reply to: T rated tires, BobS, Thu, 28 Aug 2008 19:30:20 Members do not see ads below this line. - Help Keep This Site Online - Signup |
Two advantages of lower speed rated tires - less costly and usually have a better ride. Higher speed ratings require a stiffer sidewall, which transmits more noise and vibration. Lower speed rated tires usually don't have quite the same handling.
I understand the concern about going fast, but it is instructive to understand how the tire rating test is done, and why. High speed causes heat inside the tire, and heat will cause it to break down. Heat builds up over time.
The test is performed by taking a tire and loading it to 80% of it's rated load. The speed is then increased in 10 minute steps, starting at 25 mph below the speed rating, with the final run being 20 minutes at 6 mph below the speed rating. So for a 118 MPH "T" rated tire, it is run a total of 50 minutes at speeds starting at 93 mph, with the last 20 minutes at 112 mph. After the test, the tire is examined for damage.
So even if you were to take a quick 'excursion' to 100 or 110 mph for 5 minutes, it wouldn't be anywhere near the heat buildup the tire is tested to.
Where is this a problem? If you drive at 75 or 80 mph, not really. If you regularly drive faster for long periods (10's of minutes, where heat can build up), then T rated tires aren't for you. Also, if you carry heavy loads at high speeds - 80 mph and above. Under those conditions, you might still be OK with a T rated tire, but check the load rating. Tire load ratings vary from 1000 to 2000 pounds; if you want to travel at speed with 750 pounds of drywall compound, get a better tire. And your head examined.
But if you're going to be driving at less than 80 mph, and with only brief excursions above that speed, T rated tire is probably just fine.
Here's the reference I used:
http://www.nhtsa.dot.gov/Cars/rules/rulings/UpgradeTire/Econ/TireUpgradeII.html
posted by 76.196.10...
, Thu, 28 Aug 2008 20:51:48 <-- Viewing This Message
, Thu, 28 Aug 2008 19:53:55, Fri, 29 Aug 2008 06:17:17
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