Single vs Tandem, Braked vs Unbraked: Choosing Your GT Trailer
Two of the most common questions we get about GT Trailers: should I get single or tandem axle, and does my trailer legally need brakes? Both come down to weight — here's how to work through them.
Single axle vs tandem axle
A single-axle trailer has one axle (typically two wheels); a tandem-axle trailer has two axles in line (four wheels). The choice affects more than just how many tyres you're buying:
- Load capacity — tandem axles spread the load across two axle sets, which is why GT's higher-GVM models (2000kg and up) are tandem configurations.
- Stability — tandem trailers sit flatter and tow more predictably at higher loads, particularly with an uneven or top-heavy load like a digger.
- Redundancy — if you get a flat tyre on a tandem trailer, the matching wheel on the same side generally keeps you safely mobile until you can pull over. A single-axle blowout is more serious.
- Tare weight — tandem trailers are heavier empty (more chassis, more axle hardware), which eats into your payload for a given GVM. Don't assume tandem always means more usable capacity — check the actual payload figure.
- Manoeuvrability — single-axle trailers are lighter to manoeuvre by hand and tighter to turn at low speed, which matters if you're regularly backing a trailer into a tight yard by hand.
As a rule of thumb: single axle suits lighter loads and tighter sites; tandem axle suits heavier machines, longer tows, and motorway driving where stability matters more.
Braked vs unbraked — what NZ law actually requires
New Zealand's trailer brake requirements are based on GVM (Gross Vehicle Mass — the trailer's own weight plus its maximum rated load), not on what you're actually carrying on a given day. Under NZTA's Land Transport Rule: Vehicle Standards Compliance:
| GVM | Service Brake | Parking Brake | Breakaway / Chains |
|---|---|---|---|
| Up to 2000kg | Not required | Not required | Breakaway required unless fitted with an approved coupling and safety chain |
| 2001–2500kg | Required | Not required | Breakaway required unless fitted with an approved coupling and two safety chains |
| 2501–3500kg | Required | Required (on at least one axle) | Breakaway required unless fitted with an approved coupling and two safety chains |
Two things worth knowing on top of the table above:
- Even where brakes aren't legally required, NZTA's guidance is that an unbraked trailer's laden weight shouldn't exceed three-quarters of your tow vehicle's unladen weight — and only then if your tow vehicle's brakes and tyres are in excellent condition.
- Regardless of trailer weight, the law requires the tow vehicle and trailer combination to be able to stop within 7 metres from 30km/h. A heavier trailer on a light tow vehicle can fail this even when it technically doesn't require its own brakes.
This is general guidance, not a substitute for checking your specific combination — your tow vehicle's handbook may set a stricter limit than the legal minimum, and towing capacity is also affected by your vehicle's rated towing limit and tow bar rating. If you're not sure, ask us before you buy.
Putting it together
GT's Contractor range starts at 1500kg GVM in single-axle configuration (CT8x4, CT8x5) and steps up to 2000kg tandem-axle models (CT8x5TA, CT10x5TA) for heavier or bulkier loads. The Digger range sits entirely in tandem-axle, braked territory from 2500kg GVM up, reflecting the weight of the machinery it's built to carry.
Not sure which configuration suits your vehicle and load? Get in touch — or browse the GT Contractor range and GT Digger range directly.
Source: NZ Transport Agency Waka Kotahi, Glovebox Guide to Safe Loading and Towing.
