Is there silicone in all tire dressings? Is it in trim gells too? Does it really dissolve tires? I haven't had time to detail my "blacks" the past three weeks but I've noticed a brown dirty spotty look to my tires as I walked past them. I've taken no time the last few drives to really look closely, but when I go down to drive it today I'm gonna look real close - just dirt, or rubber damage? I'm very tired now so I could just be losing it.....
I use Auto Glym products for those who wanna know and don't read the whole list. I'm not a fan of Armor All.
The original Armor All formula contained dimethal silicone fluids (DMS; solvent based). By around the late 80's they changed their product to a water based formula containing polydimethylsiloxane (PDMS). Many dressings/protectants these days use the same PDMS component.
The bad reputation AA received back in the 80's has stuck with them even today with some folks. The DMS in their product was blamed for accelerating the release of plasticizers from vinyl and rubber components causing those surfaces to "dry out". IIRC, there was even a lawsuit which likely prompted them to change the formula. In either case, the AA formulation since the late 80's/early 90's was changed to one that was water based like many other dressings/protectants today.
In Jacko’s case, the Meguiars Endurance Tire Gel he mentioned actually does contain silicone. ….DIMETHYLSILOXANE to be exact (the same DMS variant I describe above).
As far as these products actually “dissolving” your tires, I don’t know if I would use that as a description….. Tires contain a key component called an antiozonant. The purpose of this component is to help protect the rubber from drying out, cracking, etc. As you drive your car, the antiozonant from your tires migrates its way to the surface of the rubber. The result of this migration can sometimes be seen as a brownish layer/residue that appears on your sidewalls which is caused by a reaction when the chemical meets the air (often referred to as blooming). DMS based dressings have been blamed for accelerating the loss of this material from the rubber causing premature damage in some scenarios (perhaps visible as excessive “blooming”).
This “blooming” process is completely normal although some tires can be “worse” than others IME. I say “worse” (in quotes) because this component actually protects the tire yet the by product is not particularly desirable from an aesthetic point of view. Many of us will clean it off and add a dressing/protectant instead. ….I do it as well although I prefer to stick with water based products to help mitigate any potential problems.