I have found that the best way to clean tires is to scrub the h@!! out of them with a bristle brush as pictured below with the same water/vehicle soap you use for washing the paint then hose em off real good, then after they are completely dry, spray them with Armorall Protect then let that dry for a few hours, no need to wipe the access off the actual tire but wipe the overspray off the wheel. Protect is made for trim, I know, but it leaves a clean black finish that last for days "if it doesn't rain every day like it has been here
" thats not so shiny like all the tire shines. Have been doing it like this for years now and it's the only way.