Peterbilt 375/377 Deck Plates & Air Line Boxes

Frequently Asked Questions About Peterbilt 375/377 Deck Plates & Air Line Boxes

What are deck plates and air line boxes used for on a Peterbilt 375/377?

Deck plates are the flat, often diamond-textured metal panels mounted behind the cab on the frame rails, providing a durable walking surface and a mounting point for air lines, electrical cords, and other components. Air line boxes are enclosures typically mounted on or near the deck plate that organize and protect the glad hand air lines and electrical connections that run between the tractor and trailer. Together, these parts keep the back-of-cab area functional, tidy, and protected from road debris.

Will these deck plates and air line boxes fit my specific Peterbilt 375 or 377 model year?

Fitment can vary by model year and frame configuration, so it's important to check the listed specifications on each product page, including frame width and mounting hole patterns, before ordering. If you're unsure whether a specific deck plate or air line box will match your truck's setup, our team can help confirm compatibility using your VIN or existing part measurements.

What materials are these deck plates and air line boxes made from, and what finish options are available?

Most deck plates and air line boxes are constructed from steel or aluminum, with aluminum being a popular choice for its lighter weight and natural corrosion resistance. Finish options commonly include raw/mill finish, polished aluminum, or painted steel, depending on the manufacturer and product line. Polished aluminum options tend to require more routine maintenance to keep their shine, while painted or raw finishes are generally lower maintenance but may show wear differently over time.

How difficult is it to install a replacement deck plate or air line box?

Installation difficulty depends on the specific part and how it mounts to your truck. Many deck plates bolt directly into existing frame holes, making replacement straightforward with basic hand tools, while air line boxes may require disconnecting and rerouting air lines and wiring before remounting. If your setup involves custom brackets or non-standard mounting points, some fabrication or drilling may be necessary to achieve a proper fit.

Can I upgrade to a different style of deck plate or air line box than what came stock on my truck?

Yes, many owners choose to upgrade their factory deck plate or air line box to a different style, material, or design for improved durability or a customized look. Before upgrading, confirm that the new part's dimensions and mounting pattern align with your truck's frame, and be prepared to adjust air line and wiring routing if the new component has a different layout than the original.