Here's a quick displacement tutorial that shows u how to control it. Use the placement node to position it where the tread is.
Also, do a google search for tire tutorials or something of that nature. You'll find quite a bit (i couldn't find one specifically for displacement maps) and they'll help you out. Also do a search for displacement map to get more in depth with it.
Maya's help system is also a good resource. It has step-by-step tutorials, so check that out.
I apologize for the rushed post, but I didnt have time to look too much for tutorials, but you shouldn't have any problem on google.