GMC Chevrolet Silverado 2500HD 2021 Owner's Manual page 374

The outside temperature display will
default to 0 °C (32 °F) but will reset with
normal usage.
Dolly Towing
Caution
Do not tow this vehicle with two wheels
on the ground, or vehicle damage could
occur. This damage would not be covered
by the vehicle warranty.
Dolly towing this vehicle is not allowed with
either the front or the rear tires on the
ground for two-wheel drive or four-wheel
drive, regardless of transfer case.
Vehicle Care
Appearance Care
Exterior Care
Locks
Locks are lubricated at the factory. Use a
de-icing agent only when absolutely
necessary, and have the locks greased after
using. See Recommended Fluids and
Lubricants 0 393.
Washing the Vehicle
To preserve the vehicle's finish, wash it
often and out of direct sunlight.
Warning
Do not power wash any part of the
vehicle s interior, including the vinyl floor
covering. This could damage safety and
other systems in the vehicle, which
would not be covered by the vehicle
warranty.
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