When comparing truck boxes for a work vehicle, the best choice depends on where the box mounts, how often tools need to be accessed, and how much open cargo space the truck must preserve. For most pickup-based contractors, a crossover truck box is the most balanced option. For flatbeds, trailers, dump bodies, and open-deck work trucks, an underbody truck box keeps equipment secure without taking up deck space. For technicians who need fast curbside access throughout the day, a topsider truck box is usually the most efficient layout.
At American Van, we have helped professionals optimize work vehicles since 1978. This comparison focuses on four American Van truck box options: the diamond tread aluminum crossover box, the gloss black diamond tread aluminum crossover box, the diamond tread aluminum underbody box, and the diamond tread aluminum topsider box. Each is built for a different storage position, access pattern, and job-site workflow.
Quick recommendation: choose the standard crossover box for general pickup-bed tool storage, the gloss black crossover box when appearance and fleet finish matter, the underbody box when the bed or trailer deck must stay open for cargo, and the topsider box when side access is more important than centered bed storage.
Crossover vs. Underbody vs. Topsider Truck Boxes: Product-by-Product Comparison
A truck box is not just a storage container. It affects workflow, bed capacity, tool security, and how quickly a technician can reach the equipment needed for the next task. The four American Van product pages shared for this article fall into three major layouts: crossover, underbody, and topsider. Each layout solves a different storage problem.
Crossover Truck Boxes: Best for Standard Pickup Bed Storage
Crossover truck boxes span the width of a pickup bed behind the cab and rest on the truck bed rails. This design keeps the main box elevated above the bed floor, so long materials can still slide underneath in many setups. For contractors who use a standard pickup as a daily work vehicle, a crossover box is often the most balanced option because it combines strong capacity, convenient top access, and minimal bed-floor obstruction.
American Van offers two crossover options in this comparison: the Diamond Tread Aluminum Crossover Truck Box and the Gloss Black Diamond Tread Aluminum Crossover Truck Box.
- Choose the standard diamond tread aluminum crossover box if you want a classic bright aluminum finish that suits most work trucks and helps hide everyday scuffs from job site use.
- Choose the gloss black diamond tread aluminum crossover box if you want the same general crossover function with a darker, more finished appearance that pairs well with black trim, darker fleet wraps, or newer pickup styling.
- Best fit: General contractors, carpenters, electricians, plumbers, maintenance crews, and pickup-based service teams that need lockable tool storage while preserving usable bed space.
- Key buying question: Do you want the traditional aluminum look or the black powder-coated look? Functionally, both crossover choices are aimed at the same type of pickup-bed storage need.
Underbody Truck Boxes: Best for Flatbeds, Trailers, and Open Deck Space
The Diamond Tread Aluminum Underbody Truck Box is designed for a different type of vehicle setup. Instead of sitting inside or across the pickup bed, an underbody box mounts below a flatbed, trailer, or truck body. That makes it a strong choice when the top deck must stay clear for equipment, materials, pallets, or oversized cargo.
Underbody storage is especially useful for crews that carry tie-downs, chains, straps, hand tools, safety gear, or smaller accessories that need to stay secure but should not take up valuable deck space. Because this box rides lower and is more exposed to road spray and debris, its weather sealing, latch design, and mounting approach matter more than appearance.
- Choose the underbody truck box if your priority is maximizing open cargo space on the bed or trailer.
- Best fit: Flatbeds, dump bodies, trailers, landscape rigs, municipal vehicles, and hauling setups where the main deck needs to remain usable.
- Key buying question: Do you have a suitable frame or mounting location below the bed, and do you need storage that stays out of the way of large cargo?
Topsider Truck Boxes: Best for Fast Side Access
The Diamond Tread Aluminum Topsider Truck Box mounts along the top side rail of a pickup or utility body. Its main advantage is access. Instead of climbing into the truck bed or reaching across a load, a technician can stand beside the vehicle and open the box from the side.
- Choose the topsider truck box if quick curbside or roadside access is more important than a centered bed-mounted storage position.
- Best fit: Service technicians, utility crews, roadside repair vehicles, maintenance fleets, and contractors who need repeated tool access at each stop.
- Key buying question: Will your crew save time and reduce climbing by keeping daily-use tools accessible from the side of the truck?
| Feature / Specification | Standard Crossover Truck Box | Gloss Black Crossover Truck Box | Underbody Truck Box | Topsider Truck Box |
|---|---|---|---|---|
| Primary purpose | General pickup-bed tool storage | General pickup-bed tool storage with black finish | Storage below a flatbed, trailer, or truck body | Side-access storage for frequent tool retrieval |
| Mounting location | Across pickup bed rails behind the cab | Across pickup bed rails behind the cab | Beneath truck bed, flatbed, or trailer frame | On top of pickup, flatbed, or utility-body side rails |
| Best vehicle match | Full-size pickups with 6.5-ft. or 8-ft. beds | Full-size pickups with 6.5-ft. or 8-ft. beds | Flatbeds, trailers, dump bodies, service bodies | Pickups, flatbeds, and service utility bodies |
| Available sizes / model range | 18x20x71, 23x20x71, 18x27x71, and 23x27x71 in. model family 1709XXX | 18x20x71, 23x20x71, 18x27x71, and 23x27x71 in. model family 1729XXX | Multiple underbody sizes, model family 1705XXX | 16x13x72, 16x13x88, 16x13x96, 18x16x72, 18x16x88, and 18x16x96 in. |
| Technical construction details | Diamond tread aluminum, gas-shock lid opens 90°, stainless steel push-button locks, weather-resistant seals | Diamond tread aluminum with gloss black powder coat, gas-shock lid opens 90° push-button locks on both sides, pre-drilled holes and hardware included | 100-inch thick diamond tread aluminum, recessed drop door with hidden hinge locking die-cast compression latch, replaceable gasket, aircraft-grade support cables | 16-gauge steel body with 14-gauge recessed doors, gloss black powder coat, stainless steel T-handle locks, continuous hinge, weather-resistant seal, and no-drill J-hook installation. |
| Weight range listed | 64-103 lbs, depending on size | 62-103 lbs, depending on size | Varies by selected underbody size | 78-103 lbs, depending on size |
| Main advantage | Balanced access, capacity, and bed-space preservation | Same crossover utility with upgraded visual finish | Keeps the main deck open for cargo | Lets technicians access tools from beside the truck |
| Best for | Contractors carrying power tools and daily equipment | Fleets wanting a cleaner black appearance | Hauling, landscaping, municipal, and trailer setups | Service, roadside repair, and maintenance crews |
| Primary tradeoff | Occupies rail space behind the cab | Similar layout tradeoff as standard crossover | Requires appropriate underbody mounting space, brackets may be sold separately | Uses side-rail space and may affect side loading |
How to Choose the Best Truck Box for Your Job Requirements
Match the Truck Box to the Work You Do
Use this decision path when comparing the four American Van truck box options:
- Start with the vehicle type. If you drive a standard pickup, compare the two crossover boxes and the topsider first. If you run a flatbed, trailer, dump body, or open-deck work vehicle, the underbody box may be the most practical starting point.
- Decide how often tools are accessed. If tools are loaded once and used at the job site, a crossover box may be enough. If technicians open the box many times per day, a topsider can reduce climbing and reaching.
- Protect cargo space. If the truck bed or trailer deck must stay open for large materials, machinery, or pallets, underbody storage keeps tools secure without using the main cargo area.
- Consider appearance and fleet consistency. The standard aluminum crossover has a traditional work-truck look, while the gloss black crossover is better for buyers who want a darker, more uniform appearance.
- Plan installation before ordering. Crossover and topsider boxes depend on bed or rail fit, while underbody boxes require appropriate frame space and mounting hardware.
Recommended Truck Box by Buyer Type
- Best all-around pickup option: Standard diamond tread aluminum crossover truck box.
- Best pickup option for a black-finish appearance: Gloss black diamond tread aluminum crossover truck box.
- Best option for preserving open deck space: Diamond tread aluminum underbody truck box.
- Best option for frequent roadside or curbside access: Diamond tread aluminum topsider truck box.
- Best option for fleet standardization: Choose the layout first by vehicle type, then standardize finish and sizing across similar trucks.
Maintenance and Longevity Tips for Aluminum Truck Boxes
Diamond tread aluminum truck boxes are built for job site use, but basic maintenance helps preserve latch performance, weather resistance, and appearance.
- Clean the exterior regularly. Wash away road salt, mud, and job site residue with mild soap and water. Avoid harsh abrasive cleaners that can dull the finish.
- Check latches and hinges. Apply a light silicone or graphite lubricant to locks, hinges, and latch points so the box opens and closes smoothly.
- Inspect weather seals. Look for cracked, loose, or compressed seals, especially on boxes exposed to road spray or frequent rain.
- Confirm mounting hardware. Periodically inspect bolts, brackets, and rail mounts, particularly on underbody and topsider installations that experience vibration.
- Organize by access frequency. Store frequently used tools where they can be reached fastest, and reserve deeper storage space for less common equipment.
Final Recommendation
If you want a practical pickup-bed storage solution, start with the standard or gloss black crossover truck box. If you need the truck bed, trailer, or flatbed deck to remain open, choose the underbody truck box. If daily productivity depends on fast tool access from the side of the vehicle, choose the topsider truck box.
American Van provides all four truck box options reviewed in this comparison, along with broader Truck Boxes, Truck accessories, and Pickup Truck Box categories for contractors and fleets that need a complete work-truck storage setup.