Just an FYI:
Tread Wear Indicators (TWI) were mandated back in the late 1960's when vehicle regulations were first put into place. At the time, it was felt that 2/32nds was a good point - that below that value, tires became unsafe.
However, there has been a lot more research done and it has become apparent that the line where tires become unsafe is higher.
The currently thinking is that the limit should be 4/32nds for wet weather, and 5/32nds for snow.
It is unfortunate that there is not a clear cut break in the traction data. It is a smooth continuous line from full depth to zero depth, so the cut off line is somewhat arbitrary.
Tread Wear Indicators (TWI) were mandated back in the late 1960's when vehicle regulations were first put into place. At the time, it was felt that 2/32nds was a good point - that below that value, tires became unsafe.
However, there has been a lot more research done and it has become apparent that the line where tires become unsafe is higher.
The currently thinking is that the limit should be 4/32nds for wet weather, and 5/32nds for snow.
It is unfortunate that there is not a clear cut break in the traction data. It is a smooth continuous line from full depth to zero depth, so the cut off line is somewhat arbitrary.
