GMC 2012 Sierra Denali Owner's Manual page 432

10-94 Vehicle Care
Finish Care
Application of aftermarket clearcoat
sealant/wax materials is not
recommended. If painted surfaces
are damaged, see your dealer to
have the damage assessed and
repaired. Foreign materials such as
calcium chloride and other salts, ice
melting agents, road oil and tar, tree
sap, bird droppings, chemicals from
industrial chimneys, etc., can
damage the vehicle's finish if they
remain on painted surfaces. Wash
the vehicle as soon as possible.
If necessary, use non-abrasive
cleaners that are marked safe for
painted surfaces to remove foreign
matter.
Occasional hand waxing or mild
polishing should be done to remove
residue from the paint finish. See
your dealer for approved cleaning
products.
Do not apply waxes or polishes to
uncoated plastic, vinyl, rubber,
decals, simulated wood, or flat paint
as damage can occur.
Notice: Machine compounding or
aggressive polishing on a
basecoat/clearcoat paint finish
may damage it. Use only
non-abrasive waxes and polishes
that are made for a basecoat/
clearcoat paint finish on the
vehicle.
To keep the paint finish looking new,
keep the vehicle garaged or
covered whenever possible.
Protecting Exterior Bright Metal
Parts
Regularly clean bright metal parts
with water or chrome polish on
chrome or stainless steel trim,
if necessary.
For aluminum, never use auto or
chrome polish, steam, or caustic
soap to clean. A coating of wax,
rubbed to high polish, is
recommended for all bright metal
parts.
Cleaning Exterior Lamps/
Lenses and Emblems
Use only lukewarm or cold water, a
soft cloth, and a car washing soap
to clean exterior lamps and lenses.
Follow instructions under "Washing
the Vehicle" later in this section.
Windshield and Wiper Blades
Clean the outside of the windshield
with glass cleaner.
Clean rubber blades using lint-free
cloth or paper towel soaked with
windshield washer fluid or a mild
detergent. Wash the windshield
thoroughly when cleaning the
blades. Bugs, road grime, sap, and
a buildup of vehicle wash/wax
treatments may cause wiper
streaking.
Replace the wiper blades if they are
worn or damaged. Damage can be
caused by extreme dusty
conditions, sand, salt, heat, sun,
snow and ice.