Are Truck Toolboxes Waterproof?

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Toolboxes, also known as storage boxes, that can be installed onto the back of trucks come in a variety of shapes and sizes. They add storage space to help free up room on the inside of your cabin and protect your personal belongings. They are all designed to prevent the elements from damaging the things you store in them, however, they are not all made to be truly waterproof.

Waterproof or Water-Resistant?

Naturally, all toolboxes are weather-resistant and are made to keep out the rain during your travels. A large portion of them is not built to be truly waterproof. Most storage boxes, especially those on the cheaper end, do not come with an adequate amount of seals to keep out water completely.

They would fail to keep your items dry as water would leak through the unprotected openings. Unless the toolbox is advertised as a waterproof box, it is safe to assume that it is not.

In most cases, a completely airtight box is not a necessity and a regular model will fit the needs of most drivers.

Which Toolboxes Are Waterproof?

The most common types of materials that toolboxes are generally made of are steel, stainless steel, aluminum, and plastic. Each material has its strengths and weaknesses. Steel is the heaviest and most durable of these materials. However, it is the most susceptible to corrosion over time and this could cause leaks down the road.

Aluminum is lightweight and has an incredible strength-to-weight ratio. It is also an affordable metal and will be cheaper than steel, but not as durable. Aluminum is naturally resistant to corrosion and is often treated with chemicals that give it added t protection.

Plastic is the cheapest option and due to its chemical makeup, it will deteriorate slower than the other options. It doesn’t corrode and will never give rust the opportunity to create holes that allow water in. It is a good candidate to be waterproof, but it does have drawbacks. It will not be able to perform as well as its counterparts.

The material is flimsy and will be unable to carry as much weight or withstand wear and tear as well as a metal toolbox can.

Methods To Waterproof A Toolbox

If a storage box is not already waterproof, there are steps that can be taken to add protection. A black powder coating can be applied to add an extra layer of waterproofing.

A closed-cell foam gasket can be installed to better seal the opening from any lids or doors. Some toolboxes come standard with a professional seal already inside that will keep any water from getting in.

Self-closing struts can also help keep the elements at bay as they ensure your box is completely closed automatically and help prevent human error.


Toolboxes are generally designed to keep your tools, jumper cables, and other possessions safe and dry. Unfortunately, they are not all made to completely waterproof.

If a storage box does not meet this standard, a coat of black powder, an automotive-grade seal on the underside of the lid, and self-closing struts can all be beneficial in waterproofing the container.