Not that they are bald but because they were used too long and the miles , heat, ozone, oxygen have made the compound hard as a rock thus much less traction wet or dry.
Tires that have been heated [by driving on them] get progressively harder even if you stop driving on them........years not miles are the killer. Tread design and depth are over rated in consumers mind.
Personnally I don't like tires that are used over 12 months, but I know owners are trying to run them 2-3 years to save money.
Why oem tires are soft so they wear fast and don't lose too much traction before they wear out.
Bald tires are bad because
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Q45tech
- Moderator
- Posts: 14296
- Joined: Tue Apr 30, 2002 3:19 am
- Car: 1990 Q45 342,400 miles 22 years ownership with original engine
1995 G20t 5 speed 334,000 miles 16" 2002 wheels - 205/50/16 Sr20ve vvl
http://www-nrd.nhtsa.dot.gov/v...t.pdfh ... s/....html
"The proposed endurance test will be appropriately more difficult to pass, largely due to the increase in test speed from 50 to 75 mph. We support this change. Other changes from the current tests, including higher ambient temperature (+ 2°C), higher loads (+5% and +10% for passenger tires), and a longer test duration (+6 hours more than FMVSS 109), collectively toughen the requirements.
"CU believes that testing the tires for 90 minutes at 75 mph represents too short a distance (just 112.5 miles) and is well below the typical fuel range of most vehicles. Indeed, the fact that all 24 tires tested by NHTSA passed the test without failure indicates that this test is not sufficiently rigorous"
"There are no industry-wide practices for testing the effects of tire aging. Michelin submitted a proposed durability endurance test, but it would need to be run at least 250 hours, which is 1.5 to 2 weeks; the time involved to run the test would outstrip the wheel capacity of many tire manufacturers, but more important, it would seem to be too long a period of time to monitor weekly production of tires"
http://www.consumersunion.org/products/tires.htm
http://www.thecre.com/pdf/DQPaper.pdf
http://www.pitstopusa.com/TIREMEASURINGTOOLS.asp
"The proposed endurance test will be appropriately more difficult to pass, largely due to the increase in test speed from 50 to 75 mph. We support this change. Other changes from the current tests, including higher ambient temperature (+ 2°C), higher loads (+5% and +10% for passenger tires), and a longer test duration (+6 hours more than FMVSS 109), collectively toughen the requirements.
"CU believes that testing the tires for 90 minutes at 75 mph represents too short a distance (just 112.5 miles) and is well below the typical fuel range of most vehicles. Indeed, the fact that all 24 tires tested by NHTSA passed the test without failure indicates that this test is not sufficiently rigorous"
"There are no industry-wide practices for testing the effects of tire aging. Michelin submitted a proposed durability endurance test, but it would need to be run at least 250 hours, which is 1.5 to 2 weeks; the time involved to run the test would outstrip the wheel capacity of many tire manufacturers, but more important, it would seem to be too long a period of time to monitor weekly production of tires"
http://www.consumersunion.org/products/tires.htm
http://www.thecre.com/pdf/DQPaper.pdf
http://www.pitstopusa.com/TIREMEASURINGTOOLS.asp
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szh
- Posts: 15932
- Joined: Tue Jul 23, 2002 12:54 pm
- Car: 2018 Tesla Model 3.
Unfortunately, no longer a Nissan or Infiniti, but continuing here at NICO! - Location: San Jose, CA
Hi, Dennis.
Thanks for the link to precision tread depth gauges! I bought a cheaper gauge a few months ago and it seems to work pretty well, but I may get a better one if it is easier to use.
Mildly amusing story: first time I used it, I was a little taken aback at the low value. Then I realized what I had done ... I properly inserted the pin into the tread, but, totally by chance, it came down on the tread-wear indicator inside the tread! So while the tire looked like it had a fair amount of tread (about 4/32"), the reading was unusually low at 2/32".
Anyway, I am due for new tires soon and will be doing my ordering sometime soon - most likely, to fit rhe new 17x7" G35 rims I have in the garage, although I am still not sure whether to just keep my existing 15" rims on the car.
Decisions, decisions!
Z
Thanks for the link to precision tread depth gauges! I bought a cheaper gauge a few months ago and it seems to work pretty well, but I may get a better one if it is easier to use.
Mildly amusing story: first time I used it, I was a little taken aback at the low value. Then I realized what I had done ... I properly inserted the pin into the tread, but, totally by chance, it came down on the tread-wear indicator inside the tread! So while the tire looked like it had a fair amount of tread (about 4/32"), the reading was unusually low at 2/32".
Anyway, I am due for new tires soon and will be doing my ordering sometime soon - most likely, to fit rhe new 17x7" G35 rims I have in the garage, although I am still not sure whether to just keep my existing 15" rims on the car.
Decisions, decisions!
Z