Buick 2010 Lacrosse Owner's Manual page 370

The vehicle may have either
aluminum or chrome-plated wheels.
Keep the wheels clean using a soft
clean cloth with mild soap and
water. Rinse with clean water. After
rinsing thoroughly, dry with a soft
clean towel. A wax may then be
applied.
The surface of these wheels is
similar to the painted surface of the
vehicle. Do not use strong soaps,
chemicals, abrasive polishes,
abrasive cleaners, cleaners with
acid, or abrasive cleaning brushes
on them because the surface could
be damaged. Do not use chrome
polish on aluminum wheels.
Use chrome polish only on
chrome-plated wheels, but avoid
any painted surface of the wheel,
and buff off immediately after
application.