At Safari Trailers, we’ve been designing trailers for over 10 years, and we know exactly what makes a trailer durable, reliable, and built to last. In this guide, we’re lifting the lid on the things manufacturers often won’t tell you upfront—so you can build a trailer that performs exactly how you need it to.

1. Axle Position Can Make or Break Stability

Axle placement is crucial for towing safety and performance, yet manufacturers rarely emphasize its impact. A common rule of thumb is to position the axle(s) so that approximately 60% of the trailer's length is in front of the axle(s), with 40% behind. This distribution ensures proper weight balance and tongue weight, both of which are key to preventing sway and maintaining control while towing. Poor axle positioning can lead to instability, making your trailer harder to manage at high speeds or in windy conditions.

2. A Short Drawbar Saves on Materials—But Costs You Stability

Manufacturers may opt for shorter drawbars to cut material costs, but this design choice comes with trade-offs. Shorter drawbars increase instability, making a trailer more prone to swaying at higher speeds. They also make reversing more difficult, often requiring more space to maneuver accurately. Conversely, longer drawbars provide greater stability and smoother reversing, but may demand extra space when turning. Trailer manufacturers rarely highlight how drawbar length impacts handling—yet it's a key factor in ensuring a safe and stress-free towing experience. Drawbars less than 1200mm are considered short, Standard drawbar lengths range between 1200mm to 1800mm. Typically longer trailers need a longer drawbar.

3. Leaf Springs: Reliable, Cost-Effective—But Must Be Correctly Matched

Leaf springs have been the default suspension choice for centuries—dating back to Roman times—for good reason. They are cost-effective, easy to repair or replace, and highly reliable. Made from stacked spring steel plates (known as leaves), leaf springs can support large loads while reducing stress on the trailer chassis. Bolted to the axle and chassis, they create a simple yet effective suspension system.
However, matching the suspension to the trailer's total weight (ATM) is critical. If the load rating is too low, the springs will flatten and fail prematurely. Conversely, an overly stiff rating leads to a harsh ride, putting unnecessary stress on both the trailer and its load. The more leaves in the spring pack, the greater the load capacity—but choosing the right balance is key to ensuring longevity and performance.
Trailer manufacturers may not always emphasize these details, so understanding suspension specifications will help you avoid costly issues down the road.

4. The Hidden Advantage of Galvanized Trailer Decks

Manufacturers often push timber trailer decks, but what they won’t tell you is galvanized steel decks offer far greater durability, longevity, and resistance to harsh conditions.
While timber decks may be cheaper upfront, they require constant maintenance, are vulnerable to rot, and can warp over time. Exposure to moisture, heavy loads, and road grime accelerates deterioration, leaving owners with costly repairs or replacements.
In contrast, galvanized steel decks are built to last. Hot-dip galvanizing creates a corrosion-resistant barrier, preventing rust, moisture damage, and structural weakening. They withstand extreme conditions without rotting, cracking, or warping—making them the ideal choice for trailers exposed to the elements or heavy-duty use.
So why don’t manufacturers emphasize galvanized decks? Because timber decks seem more economical at first glance—but in reality, a galvanized deck pays for itself in longevity and minimal maintenance. Don’t let the hidden costs of timber decks catch you off guard—invest in a galvanized deck for real, long-term durability.

5. Welded Construction: The Gold Standard for Strength and Stability

Manufacturers may offer bolted frames as a cost-effective option, but welded construction is far superior in durability, strength, and long-term reliability. While it requires more time and skill to build, the result is a solid, seamless structure that will never rattle loose over time, even under heavy loads or extreme conditions.
Bolted frames, on the other hand, rely on bolts and rivets that can loosen with vibration, road shocks, and general wear—potentially leading to structural failure if not maintained. Welded frames eliminate this risk, creating a permanently bonded chassis that resists flexing and fatigue, ensuring a safer and longer-lasting trailer.
Yes, welded trailers cost more upfront, but that investment pays off in years of worry-free towing, reduced maintenance, and the peace of mind knowing your trailer won’t fall apart when you need it most. When manufacturers push bolted options, it’s often because it is cheaper to build and they are making more profit—not what’s best for long-term performance.

6. No Qualifications or Expensive Engineers Needed!

Anyone can build a trailer in New Zealand—but to legally tow it on the road, it must pass a Warrant of Fitness (WoF) to ensure it meets safety standards.
Registering your trailer is simple. Here’s how to do it:

• - Complete the MR2A form – This is the registration application.
• - Gather your documents – Bring your ID (e.g., driver’s license, passport) and proof of ownership if needed.
• - Pay the registration fees – Costs vary depending on the trailer type and duration.
• - Visit an authorized agent – You can register at VTNZ, AA, or an NZ Post store.
• - Get your number plate and licence label – These are issued once registration is complete.
• - Obtain a Warrant of Fitness (WoF) – A WoF ensures your trailer is road-legal.
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Build It Yourself or Let the Experts Handle It!

At Safari Trailers, we’ve been designing trailers for over 10 years, and we know what it takes to build one that lasts. That’s why we’re sharing the secrets to successfully building your own trailer, so you can do it the right way.
But if building your own isn’t quite your thing, don’t worry—we’ve got you covered! Check out New Zealand’s largest range of trailers at safaritrailers.co.nz or give us a call at 0800 378 478— we love to talk trailers!