I read on some detailing forum that Armour All can damage rubber over time unless you use it frequently due to the silicone in it. I also read that it will cause your tires to turn brown faster. I haven't paid close enough attention to my tires when I used armour all in the past, but now that I don't on my new cars, no more brown. I use the stuff from Zaino or the Endurance from Meguiers. They both shine well and last a long time.