GMC 2010 Sierra - Manual (Page 588)

Underbody Maintenance
Chemicals used for ice and snow removal and dust
control can collect on the underbody. If these are not
removed, corrosion and rust can develop on the
underbody parts such as fuel lines, frame, floor pan,
and exhaust system even though they have corrosion
protection.
At least every spring, flush these materials from the
underbody with plain water. Clean any areas where
mud and debris can collect. Dirt packed in close areas
of the frame should be loosened before being flushed.
Your dealer or an underbody car washing system can
do this.
Chemical Paint Spotting
Some weather and atmospheric conditions can create a
chemical fallout. Airborne pollutants can fall upon and
attack painted surfaces on the vehicle. This damage
can take two forms: blotchy, ring-shaped discolorations,
and small, irregular dark spots etched into the paint
surface.
Although no defect in the paint job causes this, we will
repair, at no charge to the owner, the surfaces of new
vehicles damaged by this fallout condition within
12 months or 12,000 miles (20 000 km) of purchase,
whichever occurs first.
Vehicle Identification
Vehicle Identification Number (VIN)
This legal identifier is in the front corner of the
instrument panel, on the driver side. It can be seen
through the windshield from outside. The VIN also
appears on the Certification/Tire and Service Parts
labels and certificates of title and registration.
Engine Identification
The eighth character in the VIN is the engine code. This
code identifies the vehicle's engine, specifications, and
replacement parts. See “Engine Specifications” under
Capacities and Specifications on page 6‑137 for the
vehicle's engine code.
6-128