Chevrolet Low Cab Forward 4500 2019 Series Owner's Manual page 263

262 Vehicle Care
The application of wax to rubber
component surfaces can result in
permanent whitening.
Wax must not be applied to the
windshield. Failure to observe this
precaution can result in irregular
reflection of light, impairing
your view.
Protecting Exterior Bright Metal
Parts
Bright metal parts should be
cleaned regularly to keep their
luster. Washing with water is all that
is usually needed.
Use special care with aluminum
trim. To avoid damaging protective
trim, never use auto or chrome
polish, steam or caustic soap to
clean aluminum. A coating of wax,
rubbed to a high polish, is
recommended for all bright metal
parts.
Weatherstrip Lubrication
All weatherstrips should be
periodically lubricated (minimum of
every six months) with a silicone
grease lubricant. A thin film of
silicone grease lubricant should be
applied using a clean cloth. Silicone
grease application will lengthen
weatherstrip life, help sealing, and
assist in eliminating squeaks.
Windshield Care
Wax must not be applied to the
windshield. A layer of wax can
impair your view in rainy weather
and can also lead to rough
movements of the windshield wiper.
If engine oil or grease comes into
contact with the windshield, staining
or discoloration may result. It must
be immediately cleaned away.
If not fully cleaned by the windshield
wipers, the windshield should be
cleaned using glass cleaner. If your
windshield is not clear after using
the windshield washer, or if the
wiper blade chatters when running,
wax or other material may be on the
blade or windshield.
The windshield wipers on your truck
can be pulled out from the
windshield to provide easier access
for cleaning.
Clean the outside of the windshield
with a non-abrasive cleaner. Your
windshield is clean if beads do not
form when rinsing with water. Clean
the blade by wiping with a cloth
soaked in a solution of one-half
water and one-half methanol
alcohol. Then rinse the blade with
water.
The windshield wiper arms may be
swung out, away from the glass, to
provide easy access for cleaning.
Do not hang on to the roof marker
lamps while cleaning the windshield
or damage may occur (resulting in
possible water leakage).