GMC TopKick 2007 Owner's Manual page 411

Aftermarket collision parts are also available.
These are made by companies other than GM and
may not have been tested for your vehicle. As a
result, these parts may fit poorly, exhibit premature
durability/corrosion problems, and may not
perform properly in subsequent collisions.
Aftermarket parts are not covered by your GM
New Vehicle Limited Warranty, and any vehicle
failure related to such parts are not covered by that
warranty.
Repair Facility
GM also recommends that you choose a collision
repair facility that meets your needs before you
ever need collision repairs. Your GM dealer
may have a collision repair center with GM-trained
technicians and state of the art equipment, or
be able to recommend a collision repair center that
has GM-trained technicians and comparable
equipment.
Insuring Your Vehicle
Protect your investment in your GM vehicle with
comprehensive and collision insurance coverage.
There are significant differences in the quality
of coverage afforded by various insurance policy
terms. Many insurance policies provide reduced
protection to your GM vehicle by limiting
compensation for damage repairs by using
aftermarket collision parts. Some insurance
companies will not specify aftermarket collision
parts. When purchasing insurance, we recommend
that you assure your vehicle will be repaired
with GM original equipment collision parts. If such
insurance coverage is not available from your
current insurance carrier, consider switching
to another insurance carrier.
If your vehicle is leased, the leasing company may
require you to have insurance that assures repairs
with Genuine GM Original Equipment Manufacturer
(OEM) parts or Genuine Manufacturer replacement
parts. Read your lease carefully, as you may be
charged at the end of your lease for poor quality
repairs.
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