2005 GMC Sierra Trailer Wiring | etrailer Call 800-298-8924 to get Expert Service ordering a Trailer Wiring for your 2005 GMC Sierra. Complete installation instructions and lifetime technical support on all Trailer Wiring purchases. Lowest price guarantee on accessories for your GMC Sierra and the fastest shipping available. GM Trailer Plug | eBay Genuine GM Part Number: 12191503. Trailer Tow Hitch Receptacle Plug is a direct fit for the following 2001-2015 GMC Savana 2500. 2001-2014 GMC Savana 1500.