Frequently Asked Questions About GMC TopKick Truck Deck Plates & Air Line Boxes

What years and models of GMC TopKick trucks are these deck plates and air line boxes compatible with?

Our deck plates and air line boxes are designed to fit GMC TopKick C4500, C5500, C6500, C7500, and C8500 models from 2003-2009. These parts are direct replacements for OEM components and will mount using existing factory mounting points. For earlier models (1990-2002), fitment may vary depending on your specific chassis configuration. We recommend checking your truck's VIN and contacting our support team if you have a non-standard cab configuration or custom chassis setup.

Are these deck plates made from aluminum or steel, and how thick is the material?

Most of our GMC TopKick deck plates are constructed from heavy-duty aluminum diamond plate that measures 1/8 inch (3mm) thick, providing excellent durability while keeping weight down. Some heavy-duty options feature 3/16 inch steel construction for maximum strength in severe-duty applications. All aluminum plates feature mill finish or optional powder coating, while steel versions come with a black powder coat finish to prevent corrosion. The material specifications are listed in each product description.

Do I need to drill any holes for installation, or do these use existing mounting points?

The majority of our deck plates and air line boxes are designed as no-drill installations that utilize factory mounting points and existing frame holes. Installation typically requires basic hand tools and takes 30-60 minutes per side. Some universal fit options may require minor drilling for custom applications. Each product includes detailed installation instructions, and mounting hardware is included with most items. For air line boxes, you may need to relocate existing air lines, which requires basic air system knowledge.

What styles and configurations are available for deck plates and air line boxes?

We offer several configurations including single deck plates, deck plates with integrated air line boxes, and standalone air line storage boxes. Styles range from flat diamond plate designs to formed plates with raised edges for additional storage security. Air line box options include single compartment, dual compartment, and boxes with spring-loaded doors or manual latches. Most are available in driver side, passenger side, or complete pair configurations. Custom cutouts for specific accessories can be accommodated on special order items.

Will these deck plates support the weight of toolboxes or other heavy equipment?

Our standard aluminum deck plates are rated to support distributed loads up to 300 pounds, making them suitable for most toolboxes, coolers, and equipment storage. The reinforced steel versions can handle up to 500 pounds of distributed weight. However, these are not designed for point loads or to be used as steps. For mounting heavy toolboxes, we recommend using the mounting points that tie into the frame rather than relying solely on the deck plate. Always secure heavy items with appropriate tie-downs to prevent shifting during transit.