Maximize Your RV Storage Under Your Steps with the Solid Step Storage Box

Every inch of your RV counts when you’re on the road — especially around the entry area. Your steps get used countless times and often leave unused space underneath. What if that space could become a locked, weather-resistant storage box rather than wasted volume?

The Solid Step® RV storage box #664640 slides right under your RV’s entry steps and transforms the void into a secure compartment for gear, tools, and travel essentials. It’s a clever upgrade for anyone using the Solid Step system who wants to boost storage while keeping the doorway clean and functional.

Your RV entryway isn’t just about getting in and out — it’s also prime real estate for storage. Traditional fold-down or pull-out steps leave a gap beneath the entry that often goes unused or becomes a dumping ground for odds and ends. On the other hand, the Solid Step RV storage box uses that space intentionally, turning what was an empty void into a functional cargo zone. The result is more effective use of your rig’s footprint, less clutter inside, and easier access to commonly used items without digging through cabinets.

The Solid Step RV storage box is designed to work seamlessly with your Solid Step assemblies. Here’s what you’ll find:

• Dimensions: Approximately 27.27″ long by 11.31″ wide by 13.75″ high
• Weight capacity: Up to 100 lbs of storage
• Construction: Heavy-duty steel with a durable powder-coated finish
• Ships pre-assembled with mounting brackets, hardware, and a lock with two keys
• Fits into the space where manual, flip-down steps have been removed, making it ideal if you’ve upgraded to a Solid Step entry.

In short, this is a purpose-built under-step storage solution that adds value and function to your entry system.

Upgrading your RV steps with the Solid Step RV storage box does more than simply add a box — it transforms how you use your entryway. First and foremost, you gain usable storage space without sacrificing interior square footage or requiring a bulky external box. That under-step location is convenient for stowing gear you want easy access to: leveling blocks, wheel chocks, hoses, or even outdoor accessories.

The heavy-duty steel construction and lockable lid also mean your gear stays secure and protected from weather, dust, and theft. Because the box integrates into the existing step frame, it doesn’t add awkward protrusions or look like an afterthought. The fact that it uses space that was otherwise wasted means you’re making smarter use of your rig’s architecture. Plus, when you’re focused on DIY upgrades, this box is a great match: pre-assembled, all hardware included, and designed to mount cleanly under the steps. The result is a storage upgrade that feels native to your RV rather than tacked on.

• Quick-Access Items: Instead of crawling into a cabinet for your leveling blocks or hoses, you pull them out from the box under the doorway — fast, convenient, and out of the way of foot traffic.
• Outdoor Gear Storage: Rain boots, folding chairs, and wet mats often become coat-closet chaos inside. With under-step storage, they stay in their own zone.
• Secure Storage on the Road: Because the lid locks and the box is steel-built, you can leave tools or valuables in there even when you’re away from the RV — ideal for detaching the trailer or leaving your rig unoccupied.
• Cleaner Interior Look: The box hides the structural void under your steps and prevents bags or items from piling up in that space — promoting a neater entryway and reducing tripping risks.
• Full-Time or Extended-Stay Use: If your rig stays in one spot for extended periods, this box gives you a persistent storage spot for season-specific gear (covers, tarps, expansion legs) while keeping the interior reserved for living space.

Installing the Solid Step RV Storage Box is a feasible DIY task that many RVers can tackle themselves in an afternoon.

What You’ll Need:

• Basic tools: drill, socket/wrench set, measuring tape, level
• Access to the frame/I-beam underneath your entry (requires an 8″ I-beam or equivalent per spec)
• Some space under your RV steps (previous steps removed or clearance for the box)

Remove existing fold-down step hardware if applicable. Slide the box into the void under the doorjamb and align with your chassis I-beam or mounting surface.

Use the included hardware and brackets to secure the storage box to the frame. Ensure the box is level and flush with the exterior side wall, and that the lid clears the step mechanism when open.

Open the lid and check that your entry steps deploy without interference. Confirm the box door opens fully and the lock works smoothly.

Once mounted, you can load your items (up to 100 lbs.) and lock the lid using the provided keys. Ensure items are secured to avoid shifting during travel.

Periodically check the mounting hardware for tightness, inspect the powder-coated surface for chips or rust spots, and lubricate the lock mechanism as needed.

While the Solid Step RV storage box offers strong benefits, there are situations where it may not be ideal. If your RV does not use a Solid Step® system or the void under the step is non-standard, fitment may be problematic. Some older RVs or models with limited frame clearance may require modification to mount the box flush. If you carry extremely long or oversized gear (e.g., golf clubs, oversized rods) the box size (27″ × 11″ × 13.75″) may limit what you can store. Finally, if weight is an extreme concern (every extra pound counts for a light tow rig), you’ll want to consider the 25-lb. weight of the box itself in your load calculations.

If you’re investing in an under-step storage solution, consider enhancing your entire RV entryway ecosystem for a more cohesive setup. Combine the storage box with a motion-activated step light for illuminated entry after dark, or add the Solid Step entry assist handrail for safer ingress and egress. Complement those with anti-slip treads or an all-weather entry mat to keep the doorway clean and comfortable. These upgrades work together with your RV steps to improve function, safety, and convenience in one smart package.

The Solid Step RV storage box is a highly effective way to convert unused space under your entry steps into a secure, clean, and convenient storage compartment. With heavy-duty construction, a lockable lid, and DIY-friendly installation, it checks all the boxes for a practical upgrade. Whether you’re trying to free up interior space, keep gear neatly organized, or simply make smarter use of your RV’s architecture, this under-step system delivers.

Ready to maximize your under-step storage and elevate your RV entry experience? Shop the Lippert Solid Step RV storage box #664640 today and make every step count.