I use Wesley's (simple green also helps with this, just not to the same extent) to get the tires real clean before I apply any type of shine as it cleans all the grease and such off the tires and allows the shinny stuff to stick on and last longer. However, don't use Wesley's every time you wash your car (I use it max once a month and, I drive about 1,500 miles a month) as it will tend to dry the rubber a bit if you don't apply a shine afterward.