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The browning is called blooming
I've heard it called that for over 30 years and I'm sure you have too...
...and is caused by using harsh tire cleaners and some solvent based tire dressings.
These harsh cleaners and dressings are leaching out the UV and ozone blockers to the surface of the tire causing excessive browning.
This was explained by Dr. G of Optimum.
...but, I'm not so sure I buy into Dr. G's reasoning because I just cleaned a set of tires that are several months old and have never been cleaned prior, nor dressed. I know they've not been cleaned or dressed...they're on my auto.
They had browning, but like I said, it wasn't from me using chemicals or dressing because I hadn't cleaned them prior to two days ago, nor dressed them prior to yesterday.
I have used "Bleach White Tire Cleaner" for years. You can get it just abut anywhere including Wal-Mart. Have been very pleased.
One of the greatest cleaners ever to get the brown off besides another you'll see me mention below. Those two..and only those two have worked great for me. I've tried so many more products including APC+ and Roll-Off and found other uses for them.
I've always had great results using Meguiar's Hot Rims All Wheel Cleaner on brown tires.
On more than one occasion I've had this product as well as DUB virtually ruin two sets of cleared aluminum wheels. Meguiar's wheel cleaners and me don't get along.
You're missing the point--the anti-ozonant that causes the browning is a chemical that's added to the rubber compound. Some cleaning chemicals can bring this chemical to the surface, so the more you clean, the more you bring out of the tire.
I use Optimum Power Clean now and I don't have any browning problems anymore. Other posters have made other suggestions.
Also bear in mind that different tires are different (compounded differently) and that age may play a factor as well, so generalizations about this should be viewed as just that, generalizations.
In my case, the browning started coming out of the tires after a few months having used zero cleaners or dressings...zero. As far as it being an anti-ozonant, may be.
I cleaned my tires 3 times until no brown foam was apparent. The tires were clean, but still some brown appearance near the tread remains. IF it's in fact something added from the tire manufacturer, then the brown should eventually come completely out with repeated cleanings...which I plan to start. Been much to busy in the past months caring for elderly grandparents than focusing on a clean ride. Things are changing...but I'd still rather have my grandparents back and no time for luxury cleaning.
I found D101 to not be helpful with browning problems. One OTC product that seemed pretty good was the Mothers Foaming Tire & Wheel Cleaner. Where are you located?
Besides Westley's, using Mothers Foaming All Wheel and Tire Cleaner has been an absolute pleasure. Works great on wheel cleaning as it even cleans well enough that I've found an Iron-x 2nd pass to be a waste of time. Mothers cleans the rims great and works just as good at cleaning tires. That's two bangs for one buck.