This tutorial will explain how to create the tyre tread as shown above.
You can start the treading from box modelling or splines. I personally use splines for 90% of my work, but if using splines then you will need to tidy up the model to clean up the geometry (Fig.01).
Delete half of the model so we can later mirror it. Select the faces and bevel them out enough to get some depth. Then select the edges of the model and bridge them to the other sides (Fig.02).
Instance a set of 3 in a row to make the top and bottom of the edges match up. This will help with welding the points later on (Fig.03).
Add an edit poly and hit tessellate twice. This will make the edges nice and smooth when we add a mesh smooth (Fig.04).
Add a mesh smooth modifier (Fig.05).
Add edit poly and start selecting edge loops that are not needed. Then remove them until they are on the edges, to make it smooth. I use Ctrl + Backspace to make this easier, but save often before doing this (Fig.06 - 07).
Copy the model 16 times, or however many times you need to make the treading you want. Then weld all the points that connect to turn it from 16 pieces to 1 mesh - all connected (Fig.08).
Mirror the model over, weld the middle points, and then remove the middle edge (Fig.09).
Apply a bend modifier and weld the connecting points (Fig.10).
Pull out the edges so that we can deform them outside later (Fig.11).
Apply an FFD modifier box, set it to 5x5x5 and scale in the edges (Fig.12).
Apply an edit poly and select the edges on both sides (Fig.13).
Extrude the edges in and chamfer the edges by 3 to get a smooth transition (Fig.14).
Just place the rim - and there you go! (Fig.15)
Hopefully this little tutorial will help you to model tyre tread for your own projects. This is just one of many ways to model a tyre, but I use this method the most (Fig.16).