First of all, gotta find a good picture of the tread to turn into a pattern. If you're lucky some tyre stores will have dead on shots on their website.
Next you turn it into a height map -#000000 is lowest, #FFFFFF is highest. Use gradients to create tapered parts.
From there, you can make both diffuse and NM.
Firstly, NM -
http://cpetry.github.io/NormalMap-Online/ for mine. XNormal works too. It's easy, fast and gets the job done.
Avoid the built it PS normal map generation tool as the results are terrible more often than not, it quite literally cannot output flat surfaces as perfectly flat NM.
Simply throw your heightmap into the generator and play with the sliders until you get a desired result. The default values are extremely strong so I'd suggest using up to 1 strength for tread and under 0.5 for sidewall.
Next, some noise on parts of the tread that touch the ground. Render monochrome static, make it seamless, turn into NM. Then cut a mask from the heightmap with some feather along the edges and blend with soft light mode.
That's about it for NM, diffuse is fairly straightforward.
Start with your heightmap set to multiply blend mode on a dark gray background, adjust opacity and levels if needed.
Render cloud noise, make it seamless, play with blend mode and opacity until you get a good result for the tyre you're making. (Opacity turned up in the pic to make it more visible)
Last step - I use CM for this specifically, not sure if it works if baked with Max or Blender.
Invert your normal map and use it for baking AO. It's a trick me and a friend discovered a while back.
Apply in multiply mode.
If needed, duplicate the background in multiply mode and move it to the top to darken the entire texture.
For the alpha mask (reflectivity) I just invert the heightmap and play with levels. You should add some noise to it too but I didn't bother.
