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Justin e36
11-19-2005, 01:40 AM
how exactly is tread depth calculated?

Is 8/32nds tread depth left good for Pirelli Snow tires?

J

edit: mods - please move this to the wheels & tires section.

Mystikal
11-19-2005, 03:01 AM
Tread depth is calculated as the measurement from the upper edge of tread to the base of the tire.

Winters typically come 11/32 to 13/32 new (higher performance tires come with less tread, for less squirm under load), and you typically don't want to use a winter tire with less than 6/32nds of tread remaining. So while those 8/32nd tires look pretty damn new, especially compared to summer/all-seasons, they don't really offer more than one season of good performance.

Or, to calculate their value, Pirelli snows are typically 11/32nds. Those tires have only 40% of their life left, so they should be worth 40% of the original purchase price. Also keep in mind tires lose their capabilities as they age, so 40% is being generous.

mirek
11-21-2005, 05:26 PM
how exactly is tread depth calculated?

Is 8/32nds tread depth left good for Pirelli Snow tires?

J

edit: mods - please move this to the wheels & tires section.


Pirelli says 8/32 is 35% tread used... 65% remain.

Mystikal
11-21-2005, 07:37 PM
A winter tire is no longer a winter tire when it is lower than 6/32nds. It becomes useless in snow or slush.