Points to take into consideration:
First the warnings in the Owner Manual:
From Section 10-3
Accessories and
Modifications
Adding non‐dealer accessories to
the vehicle can affect vehicle
performance and safety, including
such things as airbags, braking,
stability, ride and handling,
emissions systems, aerodynamics,
durability, and electronic systems
like antilock brakes, traction control,
and stability control. Some of these
accessories could even cause
malfunction or damage not covered
by the vehicle warranty.
Damage to vehicle components
resulting from the installation or use
of non‐GM certified parts, including
control module modifications, is not
covered under the terms of the
vehicle warranty and may affect
remaining warranty coverage for
affected parts [/color]
Not withstanding the aforementioned quote...if you live in the US there is the Magnuson Moss Warranty Act whose many provisions include in "laymans terms":
A Vehicle Manufacturer cannot void a portion of or the complete warranty by the presence and/or installation of aftermarket parts.
Does not matter if they are maintenance related (oil/filter/spark plugs/air filter etc) or accessory related (gps/ham radio/subwoofer/rims/tires etc).
However...
If the Manufacturer can show that the installation of said part caused the failure of an otherwise covered component...
or...
If the aftermarket part failed and resulted in the failure of an otherwise covered part...
a warranty repair may be excluded from coverage
Just 3 examples cause there are so many:
John Doe buys a set of aftermarket rims and tires that are larger, heavier and have a different offset and backspace than recommended by the Manufacturer. He has them professionally installed and the work is done properly. John goes into the dealer because his wheel bearings are noisey and do indeed need to be replaced. The claim is properly denied based on the rim/tire combination.
Jane Doe installs a back-up camera herself. She buys it off Ebay and it comes with everything she needs including instructions for the install in her car. She spends the better part of the day doing the install and follows the instructions to the letter. The install goes well and it's working properly and as designed. A couple weeks later there is a "melt down" of one of her fuse panels and it happens to be the one she attached the camera wiring to. However the repair required has nothing to do with and it absolutely not related to her camera installation. The car is within the time and milage of coverage for the repair and it is repaired under the coverage at no cost to her.
John Doe's brother buys an aftermarket GPS. He does the install and hooks the power lead to the back side of a "power port". Everything is fine as the circuit draw is within limits.
He then decides he is going to run another accessory using the same power port he wired the GPS to. He knows ahead of time he will need a 20Amp fuse instead of the OEM 10Amp fuse to handle the added draw. He installs the 20Amp fuse and plugs in the "other accessory". The wiring shorts out before the larger fuse blows. Result...not covered.
For more information on the Magnuson Moss Warranty Act...google is your friend
Just make sure the installation is done correctly and takes into account any warnings from the Manufacturer and you should be just fine