Product Description
Semi In-Frame Box: Heavy-Duty Aluminum Storage Behind the Cab, Step-On Rated. Made in the USA by AMERICAN TRUCKBOXES ATB®
The A-IB51B is a commercial-grade aluminum in-frame box built for semi-truck drivers and fleet managers who need secure, accessible storage mounted directly behind the cab on the truck frame. Smooth-body aluminum panels and a Diamond TP plate lid stand up to road debris and weather. American Truckboxes LLC manufactures this box in Blanchard, North Dakota, with over 25 years of heavy-duty truck box experience. Custom sizing and fleet orders are available through truckbox.com or (888) 996-0376.
- Step-on rated construction: mounts on the truck frame behind the cab and supports full standing weight for easy access to the rear of your semi
- Diamond TP plate lid: single-piece aluminum tread-plate door provides a non-slip surface and resists denting
- Smooth-body panels: flat aluminum exterior sits flush against the frame rail for a clean profile
- Stainless steel continuous hinge: full-length hinge distributes stress evenly across the lid for long service life
- Padlock lock included: bolt-style padlock hasp secures the lid and pairs with the stainless hinge for break-in resistance
- Automotive bulb-type door gasket with rain gutter: perimeter seal and gutter channel keep chains, binders, and tools dry
- Mounting kit included: comes with Mounting Kit M3100F for direct frame-rail installation
- Seven size options: 8 to 13 inches tall, 18 to 40 inches deep, all 24 inches wide
Specifications
Material: aluminum | Dimensions: 8 to 13 inches tall, 18 to 40 inches deep, 24 inches wide | Finish: smooth body with Diamond TP plate lid | Mounting: behind-cab frame-rail, step-on rated | Warranty: 60-month (5-year) limited warranty
Built in Blanchard, North Dakota by American Truckboxes LLC. Contact truckbox.com or (888) 996-0376 for custom sizing, fleet pricing, or order assistance.
Frequently Asked Questions
Q: Where is this toolbox made?
A: The A-IB51B is manufactured by American Truckboxes LLC in Blanchard, North Dakota. The company has been building heavy-duty truck boxes in the USA for over 25 years. Learn more at truckbox.com.
Q: What warranty comes with this toolbox?
A: Standard boxes carry a 60-month (5-year) limited warranty. Custom or modified boxes and auxiliary fuel tanks carry a 12-month limited warranty. The warranty applies to the original purchaser only and is non-transferable. Contact truckbox.com or (888) 996-0376 for full warranty details.
Q: Can I order a custom size?
A: Yes. Custom sizes are available directly from American Truckboxes. Custom and modified boxes carry a 12-month limited warranty. Reach the team at truckbox.com or (888) 996-0376 to discuss your dimensions.
Q: How does this in-frame box mount to my semi truck?
A: The A-IB51B mounts on the truck frame rail directly behind the cab using the included Mounting Kit M3100F. The box is rated for step-on use, meaning you can stand on it to access the rear of the truck. Installation uses standard hardware supplied in the kit.
Q: Is this in-frame box weatherproof?
A: Yes. The box uses an automotive-grade bulb-type door gasket that seals the full perimeter of the lid, paired with an integrated rain gutter that channels water away from the opening. This keeps chains, binders, and tools dry in rain and road spray.
Q: How does the lid and lock work on this box?
A: The lid is a single-piece Diamond TP plate panel mounted on a stainless steel full-length continuous hinge. A padlock hasp is built into the lid closure. The combination of a full-length hinge and bolt padlock resists forced entry better than a piano hinge with a cam latch.
Q: Which size should I choose for my semi?
A: Measure the frame opening behind your cab before ordering. The A-IB51B is available in seven sizes from 8 to 13 inches tall and 18 to 40 inches deep, all 24 inches wide. Select the size that fits your frame opening without modification. Call (888) 996-0376 if you need help matching a size to your truck.