I'm told not to use Armor-all or some of these things sold at Autozone such as Bleach White, etc as they will cause them to go yellow. I've heard Simple Green is good. Whats your input ?
I use bleche-white spray on and wipe off with generously wet cloth. They don't seem to yellow, but the whitewalls get dirty faster. Bleche-white makes the rubber soft and "sticky". The chemical melts off a lot of white, so you gotta rinse the sidewall real good.
I don't know about keeping them white, but I've used spray "Scrubby Bubbles " cleaner on them with great results. Plus they have that fresh, clean smell when you're done.
SOS pads still work but take a lot of elbow grease to make them work. DOW Chemical Bathroom Cleaner nicknamed "Scrubbing Bubbles" will clean just about anything that is dirty because it contains bleach. I tried it on my Model A Ford tires once and it bleached the yellow paint out of my acrylic enamel on my wheels. I had to repaint all of the wheels. The tire bleach still works the best for me. It is labled "Westley's Bleche-Wite". It has never damaged anything that I have accidentally got it on. I usually spray it on the white wall, then scrub the white wall with a tire brush and then I rinse it off with a garden hose. Our Skyliner is attached. Our whitewalls always look perfect.
When I am washing my cars, I clean the wheels last with the car wash soap that I am using and then spray them with Spray 9 and give them a light scrub with a scrubbing brush and rinse.