DEE ZEE DZ92656B Black (111 gallon) Black Aluminum Combo Transfer Tank & Tool Box

Why I chose this combo tank

I spend a lot of time towing and running equipment far from a fuel station, so combining diesel transfer capacity with secure bed storage made practical sense. The Dee Zee combo tank caught my eye because it promises 111 gallons in an L-shaped footprint with a bolt-on toolbox and a black powder-coat finish that blends into most truck beds. After several months of use, here’s how it has worked out on my truck and what I learned along the way.

Build, materials, and design

This is a brite-tread aluminum tank built from 0.125-inch material with a black powder-coated finish. The L-shape allows it to ride against the cab while leaving room over the rear portion of the bed for a fifth-wheel or gooseneck. At 56.25 inches long, 32.75 wide, and 25.375 tall, it occupies a meaningful chunk of bed space without feeling oversized. The powder coat looks clean and helps tame the visual busyness of diamond plate.

The integrated toolbox is bolted to the tank rather than welded, which I appreciate for serviceability. The joinery where the box meets the tank is tidy, and the weather seal around the lid has kept dust and rain out for me so far. Welds around the tank seams are consistent, and I didn’t find pinholes or spatter. It presents as a purpose-built work component rather than a showpiece, which is exactly what I want in a combo unit.

Fitment and installation

I installed the combo tank in a one-ton pickup, but its footprint works in most full-size beds. Weight planning matters: 111 gallons of diesel is roughly 770–800 pounds, plus the tank and box. That’s a lot of mass to place ahead of the rear axle, so check payload, axle ratings, and suspension before you commit to filling it to the brim.

Installation was straightforward. I positioned the unit against the front bed wall with a protective rubber strip to prevent paint abrasion, squared it to the bed ribs, and through-bolted the mounting flanges with 3/8-inch grade 8 hardware, large fender washers, and a steel backing plate under the bed for load distribution. I also bonded and grounded the system to the chassis to reduce static during fuel transfer.

The tank arrived on a pallet and was easy enough to maneuver with two people when empty. If you’re installing solo, a small gantry, forklift, or engine hoist through the bed will make it safer. I strongly recommend inspecting every surface before signing any freight receipt and photographing the unit as you unbox it. Aluminum is tough but dents easily while in transit.

As with most transfer tanks, you’ll need to supply your own 12V transfer pump and filter assembly. I fitted a 10-micron water-separating filter on the outlet and wired the pump to a fused, switched circuit at the rear of the bed with a quick-disconnect weatherproof plug.

Daily use and fuel transfer

In use, the 111-gallon capacity is the star. I primarily use it to refuel equipment on rural jobsites and to extend range when towing. With a typical 10–15 GPM pump and a clean filter, the setup turns refueling into a predictable routine. The tank breathes well; I’ve had no issues with vacuum locking or caps burping fuel during temperature swings, but I leave headspace on hot days because black powder-coat and a closed bed can heat-soak.

The L-shape does what it should: it clears the swing path for a gooseneck and doesn’t obstruct the hitch area. Sight lines from the cab are largely unaffected. I can open the toolbox lid fully without contacting the rear window, and the lid stays put while I work.

If you’re considering using it to gravity-feed the truck, plan on proper plumbing, a shutoff at the tank, and attention to local regulations. I use it strictly as a transfer tank for diesel and dyed diesel to keep compliance simple.

The toolbox: space and usability

The bolt-on toolbox offers generous, usable volume. I can stow larger items—cordless saws, a compact inverter generator, a small air compressor—plus hand tools and consumables, with room left over for spares. The black powder coat reduces glare and looks sharp, and the weather seal has kept wash water and dust out during long gravel drives.

A couple of caveats. First, there’s no built-in tray or organizer. I ended up adding a removable bin system and non-slip drawer liner to keep smaller items from skating around. Second, the lid skin and box walls are aluminum; they’re not flimsy, but they’re not a workbench either. Don’t kneel on the lid while installing a pump, and avoid resting heavy, point-loaded items on it. If you expect to routinely stand on your toolbox, you’ll want to add a support plate or choose a heavier-duty lid.

The latches engage cleanly and the lock cylinders have stayed aligned. If you’re in a high-theft area, consider adding a secondary hasp or a concealed cable lock point inside the box, because any aluminum box is ultimately a delay device, not a vault.

Durability and finish

The .125-inch tank body is appropriately stout for mobile use, and the powder coat has resisted chipping and corrosion so far. Black hides the usual scuffs better than raw aluminum but will show light rub marks if you’re sliding pallets up against it; a quick wipe with a polymer detail spray brings back the uniform sheen.

My unit arrived clean and straight, but aluminum is susceptible to shipping dings. This is one of those products where packaging quality matters, and it’s worth taking your time during delivery inspection. In day-to-day service, the tank has stayed tight, with no seepage at fittings and no drips at the cap. I re-torque mount bolts after the first week and again after a couple of months as the bed liner compresses.

Safety and compliance notes

A few quick reminders I follow with any transfer tank:
- Diesel only. Do not use for gasoline or alcohol blends unless the tank is explicitly rated and labeled for it.
- Use a proper filter and bonding/grounding during transfer to control static.
- Leave expansion headspace and park level when filling.
- Secure hoses and nozzles to prevent chafe and accidental discharge.
- Verify local and state regulations for mobile fuel storage and transfer.

These aren’t unique to this unit, but the capacity amplifies the importance.

What I liked

• Big capacity in a manageable footprint; the L-shape plays nicely with goosenecks and fifth-wheels.
• Solid 0.125-inch aluminum tank with a clean black powder-coated finish.
• Bolt-on toolbox adds real-world utility and stays dry.
• Straightforward install with conventional hardware; easy to pair with a 12V pump and filter.
• Good ergonomics: lid access is generous, and the box doesn’t crowd the cab window.

What could be better

• No organizer tray; plan to add bins or a divider system.
• Aluminum lid and box skin flex if you kneel or stand on them; treat it like a storage lid, not a platform.
• Watch for shipping dings; inspect and document during delivery.
• At full capacity, it eats payload quickly—plan your load and suspension accordingly.

Who it’s for

If you run diesel equipment, tow long distances, or simply want to cut fuel-station detours, this combo tank makes day-to-day work smoother. It’s best suited to three-quarter-ton and one-ton trucks where payload margin isn’t a constant fight. If you need a toolbox you can climb on regularly, or if your use case demands the absolute toughest lid and walls, you may want to look at heavier-lid alternatives or plan some reinforcement.

Recommendation

I recommend the Dee Zee combo tank for diesel owners who want substantial auxiliary capacity with the convenience of an integrated, weather-resistant toolbox. It strikes a practical balance: a sturdy, .125-inch aluminum tank where it matters and a lightweight—but serviceable—box for tools and consumables. Install it thoughtfully, add your own organization inside the box, and treat the lid with reasonable care, and it will pull its weight day in and day out. The capacity, fit with towing setups, and clean powder-coated finish make it a smart upgrade for work trucks that actually work.