It does if you have a GPS speed input. In the race car daq I use I can see speed differentials due to tire wear. A typical 17" tire has a radius of 318 mm and

It does if you have a GPS speed input. In the race car daq I use I can see speed differentials due to tire wear. A typical 17" tire has a radius of 318 mm and 8 mm of tread. So a bald tire is 2.5% smaller than a new one.