Here at GM Parts Headquarter we want to make your GMC parts ordering experience as easy as possible. So if you cant find the replacement 2012 GMC Sierra 3500 HD part you need, feel free to contact us! We can help you place an order. All of our replacement 2012 GMC Sierra 3500 HD WT parts are backed by a nationwide warranty accepted at any GMC dealership. So sleep easy knowing your replacement part is covered!