How Do I Mount A Truck Tool Box With An Existing Tonneau Cover?

Adding extra storage space to your truck with a tool box is a great idea. But what if you already have a tonneau cover installed? Is it still possible to mount a truck tool box? The answer is yes! With some planning and adjustments, you can mount a tool box with a tonneau cover already in place.

What Types of Tool Boxes and Tonneau Covers Are Compatible?

The first step is choosing a tool box that is compatible with your tonneau cover. There are a few considerations:

Type of Tonneau Cover

• Roll-up covers: These vinyl covers roll up and can be strapped behind a tool box when not in use. They work well with over-the-rail tool boxes that sit on top of the truck bed rails.
• Folding covers: Hard folding or soft tri-fold covers need to be removed to install a tool box in most cases. They can be reinstalled after the tool box is mounted.
• Retractable covers: These rigid covers retract on rails or into the cab. Like roll-ups, they are usually compatible with over-the-rail boxes.

Style of Tool Box

• Over-the-rail: These tool boxes sit on top of the bed rails, making them ideal for use with roll-up or retractable tonneau covers. They are usually aluminum or polymer construction.
• Crossover: Crossover boxes have a front section that sits over the bed rails and a main compartment recessed down into the bed. They work with some folding covers.
• Underbed: These low-profile tool boxes mount underneath the truck bed, so they are hidden by the tonneau cover. Good for any cover type.
• Chest boxes: Large chest-style tool boxes take up most of the truck bed. Generally they require removing any existing tonneau cover.

Check Manufacturer Specifications

Once you’ve narrowed down the tool box and cover styles, double check that they are compatible according to the manufacturer specifications. Most will indicate if they are designed to work together or have special mounting requirements.

Position and Mount the Tool Box

Once you have compatible gear, it’s time to mount the tool box:

Place the Tool Box in the Truck Bed

• Center the tool box side-to-side in the bed.
• Make sure it is straight and the edge is flush with the inside lip of the bed on both sides.
• Position it as close to the cab as possible to maximize usable space.

Secure the Tool Box

• For an over-the-rail box, use J-hooks that attach to the bed rails to hold it in place.
• Underbed boxes usually bolt through the truck bed floor.
• Follow the manufacturer’s instructions to ensure a secure mount.

Adjust the Height (if needed)

• Some mounting systems allow you to adjust the tool box height.
• Make sure the tonneau cover will close properly without hitting the toolbox once installed.
• The optimal height provides just enough clearance underneath for the cover.

Work With the Tonneau Cover

Now it’s time to deal with the tonneau cover:

Roll-up Tonneau Covers

• Simply roll up the vinyl cover and strap it in place behind the tool box using the provided straps.
• When you want full bed access, unstrap and unroll the tonneau cover.

Hard Folding Tonneau Covers

• Most hard folding covers need to be fully removed to install an over-the-rail or crossover style tool box.
• Once the toolbox is in place, reinstall the panels of the cover. Make sure the sections fold properly around the tool box.
• Some covers may require trimming or modifications to the panels. Check fit and alignment before permanently reinstalling.

Soft Folding Tonneau Covers

• Like hard covers, soft folding covers usually need complete removal before mounting the tool box.
• After mounting the toolbox, reinstall the panels. Make sure the vinyl folds correctly around the toolbox.
• You may need to trim the vinyl or make other adjustments for proper fit.

Retractable Tonneau Covers

• If your retractable cover is designed for over-the-rail tool boxes, simply install the toolbox on the bed rails.
• Make sure the cover can retract fully with the toolbox in place.
• Adjust the box position or cover roller assembly if needed.

Underbed Storage Systems

• If you choose an underbed toolbox that mounts low inside the truck bed, it can be used with any tonneau cover already installed.
• The cover rests right on top of the recessed toolbox. Just be sure to account for the reduced bed depth.

Tips for a Clean Installation

Follow these tips for a secure and integrated toolbox installation:

• Use quality, heavy duty J-hooks or mounting hardware. Don’t skimp here.
• Make sure all contact points are flush and properly supported.
• Follow torque specs for all bolts and hardware. Overtightening can damage components.
• Seal any holes in the bed with silicone. Prevent moisture entry and rust.
• Apply paint/primer to any drill holes or scraped areas. Maintain the finish.
• Try shims or spacers if needed between the toolbox and rail for proper alignment.
• Always check that the tailgate shuts properly without hitting the toolbox.

The Benefits of Adding Truck Bed Storage

Once you have your toolbox mounted, you’ll be able to enjoy the many benefits these storage systems provide:

• More secure storage than a basic bed cover. Toolboxes lock, so your cargo is protected.
• Keep tools, gear and other equipment organized and damage-free.
• Added cargo capacity without sacrificing bed length or usability.
• Quick access to your stuff when needed on a job site or adventure.
• Protect valuables from weather and rust/corrosion.
• Certain tool storage combos even have work surfaces, power ports, and interior lighting.
• Higher resale value — truck boxes are an attractive extra feature.

With a little planning and effort, you can mount a truck toolbox regardless of your existing tonneau cover. Just follow the tips above for a secure, integrated installation. The added storage and organization will make the upgrade well worthwhile. Now you can keep all your truck gear safely stowed and easily accessible.

Frequently Asked Questions About Mounting a Toolbox with a Tonneau Cover

What are the most compatible toolboxes and tonneau covers?

Roll-up tonneau covers pair best with over-the-rail toolboxes. Retractable covers also typically work with over-the-rail tool boxes. Under-bed systems are universally compatible. Hard folding covers are the most limiting, often requiring custom work or modifications.

How do I secure an over-the-rail toolbox?

Use heavy-duty J-hooks that attach to the bed rails to hold the toolbox firmly in place. Follow the manufacturer’s mounting instructions. Make sure it is centered, level, and flush with the bed rails.

What if my toolbox hits my folded tonneau cover?

Try adjusting the box height/position or cover mount points. You may need to trim cover panels or modify the mounting brackets. An over-the-rail style box improves compatibility.

Can I still open my tailgate with a toolbox installed?

Check the clearance between the lowered tailgate and rear of the toolbox. If they hit, reposition the box further forward in the truck bed to allow full tailgate operation.

Will a toolbox affect my truck’s fuel economy?

A mid-sized aluminum toolbox adds negligible aerodynamic drag. Under-bed systems have no effect. Larger chest-style boxes may decrease MPG slightly. But convenience often outweighs minor fuel economy impacts.

How do I maintain my toolbox’s finish?

Use automotive wax on the exterior to protect the finish. For scratched or damaged areas, clean, prime and paint using touch-up paint that matches your toolbox color. Keep the interior clean and dry.

How can I secure the contents inside my toolbox?

Many truck toolboxes feature keyed lock mechanisms on their lids to securely store your cargo. You can also install a small safe or lockbox inside the main compartment for extra security. Use hooks to keep tools and gear organized.

What are toolboxes made out of?

Most truck toolboxes are constructed from aluminum or polymers like polyethylene. Aluminum provides durable strength while remaining lightweight. Plastic polymers offer excellent dent and rust resistance. Higher end boxes feature sturdy, aircraft grade aluminum.

In Conclusion

Adding extra cargo capacity to your truck with a toolbox is a great upgrade. And you don’t have to remove your existing tonneau cover to mount most toolboxes. Roll-up and retractable covers are generally the most compatible options. Hard folding covers may require some customization or adjustments.

Following the right mounting, positioning, and installation steps is key to integrating your toolbox with the tonneau cover. With the right box and installation method, you can safely haul and secure more gear for work or play.