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Your complete satisfaction is important to us, and we’re here to help. Please mail your comments, questions or concerns to one of the following Customer Assistance Centers:
In the United States:
GMC Customer Assistance Center
P.O. Box 33172
Detroit, MI 48232-5172
In Canada:
Canada - GM of Canada
1908 Colonel Sam
Oshawa, Ontario
L1H 8P7, Canada
Mail Code 163-055