Tires: tire rotation, directional tires, tire treatment

Question
I have firestone destination le  on a f-150, what rotation pattern do i use? ford manual suggests x-ing the front left to the right rear and the rear left to the front left,x-ing the front right to the rear left, and the rear right to the front right, would this be the correct pattern for THESE TIRES? Also me side walls are showing like a milky white in the rubber that wont wash off/out, any ideas to what this could be, I use Mcquires Tire Shine, I only have three tires doing this.

Answer
Chris,

Any rotation pattern is better than none at all.  The best pattern is the one you described (commonly called a Modified X).  The only exceptions to this are when you can not rotate in an X - like when you have directional tires or the tires are different sizes front to rear.

But the rotation pattern has a very small effect in the big scheme of things.

The white stuff is probably a wax that is migrating to the surface.  It protects the surface from UV rays and oxygen.  But it's possible the the tire treatment is accellerating the process.  This will gradually fade away as the tire gets older.