Buick RIVIERA 1993 Manual page 259

Aluminum Wheels
If your Buick has these, don't use chrome polish on
them. Use wax after you clean them. Also, don't use
abrasive cleaners or cleaning brushes on them
--
you
could damage the protective coating.
White Sidewall Tires
Your Buick dealer has a GM White Sidewall Tire
Cleaner. You can use a stiff brush with
it.
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