8.5x20 Double Axle with Ramp Door

Choosing the right enclosed cargo trailer is a significant investment, one that directly impacts your efficiency, security, and capability. For those needing a blend of substantial space, robust capacity, and versatile access, the 8.5x20 double axle trailer with barn doors emerges as a premier choice. This configuration isn’t just a box on wheels; it’s a mobile solution engineered for contractors, car enthusiasts, business owners, and serious hobbyists alike. The global demand for such versatile hauling solutions is on the rise, with the cargo trailer market estimated at approximately USD 8.5 Billion in 2024 and poised for continued growth. This guide is designed to navigate you through every critical aspect of selecting the perfect trailer, transforming a potentially complex decision into a clear and confident choice.

Why an 8.5x20 Double Axle Trailer? The Foundation of True Versatility

The 8.5x20 size hits a sweet spot, offering ample interior volume without becoming unmanageably large for most tow vehicles. It’s spacious enough for a classic car, a full load of contracting equipment, or inventory for a mobile business. The double axle (or tandem axle) design is the cornerstone of its capability, providing superior stability, enhanced weight distribution, and a crucial safety redundancy that single-axle trailers simply cannot match. This combination of size and strength makes it one of the most adaptable and popular enclosed trailer models on the market.

What You’ll Learn in This Guide: From the Essentials to Customization

This ultimate guide will demystify the selection process. We will dissect the fundamental components, from frame construction to axle types. You’ll gain a clear understanding of why barn doors might be the ideal choice for your needs compared to a ramp door. We will explore key features, must-have specifications, and the world of custom options that allow you to tailor a trailer perfectly to your unique requirements. By the end, you’ll be equipped with the knowledge to make an informed investment that serves you reliably for years to come.

Understanding the Basics: What Exactly is an 8.5x20 Double Axle Trailer?

Before diving into the finer details, it’s essential to grasp the core terminology and components that define this powerful hauling tool. Understanding what “8.5x20” means and why the double axle is so critical will form the foundation of your decision-making process.

Dimensions and Capacity: Making Sense of the “8.5x20” Designation

The “8.5x20” designation refers to the trailer’s primary interior dimensions: 8.5 feet (or 102 inches) in width and 20 feet in length. This provides a substantial footprint of 170 square feet of floor space. However, the usable space is also defined by the interior height, a critical factor often ranging from a standard 6’6″ to 7′ or more, which determines the types of vehicles or stacked cargo you can accommodate. These dimensions, combined with the trailer’s Gross Vehicle Weight Rating (GVWR), dictate its payload capacity—the total weight of the cargo it can safely carry.

The Double Axle Advantage: Experience Enhanced Stability, Capacity, and Safety

The double axle configuration is a non-negotiable feature for a trailer of this size. The presence of two axles working in tandem offers several profound advantages. According to market analysis, the tandem axles segment dominated the trailer axle market in 2024 due to its superior performance benefits. First, it dramatically increases the trailer’s weight-carrying capacity. Second, it distributes the load more evenly, leading to a much smoother and more stable towing experience, especially at highway speeds and in crosswinds. Finally, it provides a critical layer of safety; if one tire fails, the second tire on that side can support the load, allowing you to pull over safely.

The Barn Door Advantage: Why This Configuration is an Excellent Choice for You

The choice of rear door is one of the most significant decisions you’ll make. While ramp doors are common, the double rear doors, often called barn doors, offer a unique set of benefits that make them the superior choice for many applications. Reflecting their growing appeal in various industries, the broader barn door market is projected to grow at a CAGR of 5.7% from 2025 to 2033.

Barn Doors vs. Ramp Doors: A Detailed Comparison

A ramp door is a single, large panel that hinges at the bottom and lowers to the ground, creating a ramp for rolling cargo. This is ideal for vehicles with low ground clearance.

Barn doors, conversely, are two doors that swing outward from the center. Their advantages include:

• Tight Space Loading: They allow you to back up directly to a loading dock or get closer to a building without needing clearance for a ramp to extend.
• Forklift Accessibility: The wide-open access makes it significantly easier to load and unload pallets or heavy equipment with a forklift.
• Durability and Simplicity: With fewer moving parts and no spring-assist mechanisms, barn doors are often more durable and require less maintenance over time.
• Weather Protection: You can open one door at a time to retrieve items, minimizing the exposure of your cargo to rain or snow.

The primary trade-off is the need for separate ramps if you plan to load wheeled equipment or vehicles.

Perfect Uses for Barn Door Trailers

The barn door configuration excels in specific scenarios. Contractors love the ease of forklift loading for materials like lumber or drywall. Landscapers and construction crews can back directly up to job sites to unload heavy machinery. Mobile businesses, from pop-up shops to service technicians, benefit from the dock-level access and the ability to operate in confined spaces. For general cargo and palletized goods, the barn door is the undisputed champion of efficiency.

Key Features and Specifications for Top-Notch Performance

A high-quality enclosed trailer is more than just its dimensions; it’s a system of carefully engineered components working together. Understanding these key features will allow you to assess the quality, durability, and value of any model you consider.

Structural Integrity: Examine the Frame, Exterior, and Roof

The trailer’s backbone is its frame. Look for a robust Tube Frame construction, particularly for the main rails and wall uprights, as this offers superior strength and rigidity compared to C-channel or Z-channel designs. Heavy-duty I-Beam Main Rails are often used on larger models for maximum durability. The exterior should be protected by a durable asphalt undercoating paint to resist corrosion from road salt and moisture. For a clean, modern aesthetic and easier decal application, a screwless exterior is a premium option. Protecting the top is a one-piece Galvalume Roof, which provides excellent, long-lasting resistance to rust and leaks.

Interior Design and Functionality: Maximize Your Trailer’s Usable Space

Inside the trailer, functionality is paramount. A 3/4-inch Plywood Floor is the industry standard for strength and durability, capable of withstanding heavy loads and equipment. Easy access is crucial, which is why a well-placed side door (typically 32-36 inches wide) with a secure lock is a standard feature, allowing you to enter the trailer without opening the large rear doors. For visibility, at least one LED Dome Light is essential, providing bright, efficient illumination so you can work safely inside, day or night.

Running Gear: Axles, Tires, and Wheels for a Smooth, Reliable Ride

The running gear is where the rubber meets the road—literally. For the smoothest ride and best protection for your cargo, a Torsion Axle system is a significant upgrade over standard leaf springs. Torsion axles provide independent suspension for each wheel, absorbing bumps more effectively. The trailer should be equipped with high-quality radial tires, which run cooler, last longer, and offer better fuel economy than older bias-ply designs. Check for a 6 Ply rating or higher, ensuring the tires can handle the trailer’s intended load. These tires can be mounted on standard Powder Coated Modular Style Steel Rims or upgraded to lighter, more stylish aluminum wheels.

Ensuring Safety, Visibility, and Protection on the Road

Safety is non-negotiable. A quality trailer will feature bright, long-lasting LED lights all around, including the crucial LED Tail Lights, ensuring you are visible to other drivers. At the front, a durable Stone Guard, typically made from Aluminum Tread Plate (ATP), protects the trailer’s face from rocks and debris kicked up by the tow vehicle. The electrical system connects to your vehicle via a standard 7-way Round plug, which operates the trailer’s electric brakes and all trailer lights. Finally, a heavy-duty Tongue Jack is essential for easily hitching, unhitching, and leveling the trailer when it’s not connected.

Customization: Tailor Your Enclosed Trailer to Meet Your Unique Requirements

One of the greatest advantages of buying a new enclosed cargo trailer is the ability to customize it. Standard models provide a fantastic baseline, but custom options transform a generic trailer into a specialized tool designed specifically for your needs, whether you’re creating the ultimate car hauler or a mobile workshop.

Exploring Popular Customization Options

The list of potential upgrades is extensive. You can increase the interior height for taller vehicles, add extra D-rings and E-track systems for versatile cargo securement, or reinforce the floor and add a ramp door flap for heavy-duty applications. Other popular options include upgrading to an electrical package with outlets and overhead lighting, installing windows for natural light, adding vents for air circulation, or choosing from a variety of sample colors to match your business branding or tow vehicle.

Designing Your Personalized Trailer: From Vision to Reality

Start by clearly defining your primary use case. If you’re building an enclosed car hauler, consider options like a beavertail floor for easier loading, an escape door over the fender, and ATP or rubber coin flooring. For a contractor trailer, think about built-in shelving, ladder racks, and a generator compartment. Work with your dealer to review all available options, balancing your needs with your budget to create a trailer that is perfectly equipped for the job from day one.

Navigating the Buying Process: From Research to Road-Ready Registration

Purchasing your trailer involves more than just picking features. A smooth buying process requires attention to budgeting, understanding legal documentation, and performing crucial inspections to ensure you’re getting a quality product.

Budgeting and Financing Your Important Investment

Establish a clear budget that includes the base price of the trailer, any customizations, and additional costs like taxes, registration fees, and delivery. Many reputable dealerships offer financing options, allowing you to spread the cost of this important investment over time. Be sure to get a detailed, itemized quote that lists all standard features and your chosen upgrades to avoid any surprises.

Understanding Your VIN: Essential Identification and Legal Information

Every legally manufactured trailer has a unique 17-digit Vehicle Identification Number, or VIN number. This number is critical for registration, insurance, and tracking. It contains coded information about the manufacturer, trailer model, and year of production. Ensure the VIN on your bill of sale matches the VIN plate on the trailer itself.

Pre-Delivery Inspection and Warranty: What to Look For to Ensure Peace of Mind

Before you take delivery, perform a thorough inspection. Check that all doors latch securely, all trailer lights function correctly, and the brakes engage. Look over the welds, sealant, and overall fit and finish. Confirm that all your custom options have been installed correctly. Most importantly, understand the warranty. A reputable manufacturer will offer a structural warranty (often 3-5 years) and warranties on individual components like axles and tires.

Registration and Legalities for Your New Trailer

Once you’ve purchased the trailer, you’ll need to register it with your state’s department of motor vehicles. You will typically need the bill of sale and the Manufacturer’s Certificate of Origin (MCO). Be aware of your state’s requirements regarding titles, license plates, and any annual inspections for a trailer of this size and weight.

Caring for Your Investment for Long-Term Durability

Your 8.5x20 double axle trailer is a valuable asset. Proper care and routine maintenance are essential to protect your investment, ensure its safety on the road, and maximize its lifespan.

Essential Routine Checks and Proactive Maintenance

Periodically check tire pressure and inspect for wear. Test all LED lights and the 7-way round plug connection before each trip. Check and adjust the trailer brakes as needed. Regularly lubricate moving parts like door hinges, the tongue jack, and the coupler. Inspect the suspension components and ensure lug nuts are torqued to the manufacturer’s specification.

Tips for Protecting Your Trailer’s Exterior and Interior Surfaces

Wash the trailer regularly to remove road grime, salt, and dirt that can lead to corrosion. Pay special attention to the undercarriage where the asphalt undercoating provides protection. Inspect the roof seams and sealant annually, touching up any areas that show signs of cracking or peeling to prevent leaks. Inside, keep the plywood floor clean and dry to prevent rot and delamination.

Seasonal Maintenance for Continued Peak Performance

Depending on your climate, you may need to perform seasonal maintenance. In winter, ensure the undercarriage is cleaned frequently to remove corrosive de-icing agents. In summer, check tires more often as high temperatures can increase pressure. If storing the trailer for an extended period, consider covering the tires to protect them from UV damage and placing the trailer on jack stands to take the weight off the suspension and tires.

Conclusion: Your Ideal 8.5x20 Double Axle Trailer is Within Reach

Selecting the perfect 8.5x20 double axle trailer with barn doors is a journey of matching robust engineering with your specific needs. This guide has equipped you with the foundational knowledge to navigate that journey confidently. From the unyielding strength of a tube frame and the smooth ride of torsion axles to the unparalleled access of double rear doors, you can now dissect specifications and identify true quality.

Key Considerations to Remember

As you finalize your decision, focus on the core elements: structural integrity, a reliable running gear, and a functional layout tailored to your purpose. Don’t underestimate the value of a convenient side door, bright LED lights, and protective features like a stone guard. Whether you need a standard enclosed cargo trailer or a highly customized car hauler, the right combination of features is available. By investing in a well-built, thoughtfully specified trailer, you are acquiring a durable tool that will deliver value, security, and performance for countless miles and many years ahead.