Test: Stewart Trailer NZ5500

The NZ 5500 has been specifically designed for the Kiwi market by Scottish-based Stewart Trailers

James and Mandy Stewart first started the company in 1988 in the Scottish midlands and have grown it from strength to strength, remaining nestled in the productive and fertile lowlands of Aberdeenshire County. The Stewart name has forged a reputation for exceptional build quality and bespoke trailer design to meet unique markets – something I discovered during a recent trip to the Manawatu to see the newly arrived NZ5500.

The story behind the NZ5500

Stewart trailers NZ5500 is the Scottish-built Stewart trailer designed specifically for the Kiwi market. The guys at TRC tractors in Fielding and Ikon Machinery in the South Island sat down with some large contracting clients and asked them what they needed and wanted in their ideal trailer. Then they set about making that happen.

Feedback was consistent and included a long deck, a fixed headboard, the ability to add a hay extension plus gravel sides and a silage bin – all making for a highly versatile trailer. Unlike our European counterparts who are accustomed to having a separate machine for each job, Kiwi farmers and contractors love the ability to have one piece of machinery that can do a multitude of jobs.

The TRC team then passed on the feedback to James Stewart and said we need to get the Etch a Sketch out fella – and the NZ5500 was born. The name is directly linked to the length of the trailer. It is 5.5 metres long and also designed a little wider to allow it to comfortably fit two bales side by side the
2.7-metre deck.

While this is exactly what the Kiwi contractors were after, it has created a small problem – the NZ5500 now no longer fits in a container; it’s a roll-on/roll-off operation. While this may be slightly more expensive, given the rising price of containers plus container shipping delays and the fact they now come fully assembled and get here faster, that cost difference becomes negligible.

Also looking to keep the cost of manufacturing down, Stewart Trailers have used its existing bathtub 16-tonne trailer chassis and running equipment. Above the chassis is all new and improved, however, while below the deck is time-tested reliability.

During our test, we were with the Pilet Contracting team near Marton, who had taken delivery of their second Stewart NZ5500 trailer in as many days. After 30 years in the industry, Craig Pilet couldn’t be happier with how the initial conversation had turned into reality.

Deck and chassis

Stewart Trailers’ moto is ‘Bigger, stronger, tougher’, and the NZ5500 – on the face of it – certainly lives up to that. If we start at the drawbar, it has a piece cut out of it and then pressed down and welded, so you don’t actually end up with any structural loss but can maintain a sloping narrow drawbar. This is particularly great for tight turning.

Then for comfort, two large springs take care of the drawbar suspension and work great to take both the shunting and pitching out of a fully-loaded trailer.

The chassis on the Stewart was a real revelation. The large box section chassis is not a new feature on tip trailers, but I was impressed at the tipping chassis being tucked inside the main chassis rails. I can see two great benefits here. First, it keeps a low overall height, which keeps the centre of gravity down and, in turn, aids massively in the stability of the trailer on hills. Secondly, because it makes the trailer tilt slightly backwards, it makes the initial push from the twin chrome plates tipping rams much easier, dropping the overall tipping height and significantly reducing the risk of chassis twisting.

Main deck

The entire main deck is Hardox, and the name speaks for itself. It’s one of the most durable metals on the market and given that these things get a hiding from diggers and large chunks of metal being dropped, is an important feature. Also of note is that the cross members under the deck are closely spaced. This means that if a hard rock does hit the deck, the Hardox will firstly protect and secondly because there’s a lot of strength underneath the steel, it means you don’t end up with dents and waving in the deck, which is something that holds water, resulting in a loss of strength.

Gravel sides

The two-piece removable gravel sides are also Hardox with their own hydraulic high lift tail door. The sides are made pressed to hug the side and floor of the trailer, with large gussets and strengthening to handle the 16-tonne metal capacity. Craig loves the
steep tipping angle and high lift tailgate particularly for drain cleanings with sticky Manawatu clay – he reckons it works a treat.

Silage bin

The one-piece crate with its own hydraulic door can be lifted on and off with a Hiab or telehandler in minutes. Again, this features the overlap on the sides with a folded edge, which simply bolts down. This adds a lot of strength to the trailer and makes it easy to quickly take on and off. The crate bolsters capacity to 34 cube and a large Perspex screen at the front allows easy visibility from the cab during loading.

Axles and brakes

Most European trailers are equipped with high-speed axles, and this is no different on the Stewart NZ5500. The Granning commercial 10 stud axles come with 420×180 brakes on both axles in either air or hydraulic configuration (or both). However, these are sprung slightly differently to some other trailers. They use four large leaf springs, which still give great ride comfort but are much stronger than a larger number of smaller leaf springs U bolted to the axle. They also don’t flex as much so you don’t get that sideways swaying, particularly on hills, which tends to make the trailers dangerous.

Then there’s the large 560mm wide tyres that do two things. First, they have a large rolling circumference that makes it easier to pull, and secondly, ground conditions in the Manawatu and other parts of the country can be marginal, particularly in early spring. That’s why these tyres with low ground compaction and easy pulling characteristics make for great silage trailers.

Easy living everyone

It’s all well and good to have a ritzy looking trailer but it also needs to be long lasting and easy to live with on the daily. Luckily, the Stewart has both: the two LED beacons at the back, large well-protected taillights, rear mud flaps, and secure tie rails make it look the part. It also has the impressive Flexi paint, helping make these trailers continue to look new for years.

The centralised grease bank is great for daily maintenance. The grease bank is at waist level and covers everything apart from the tail door rams and pivots on the gravel sides and silage bin. While serviceability is easy, it’s also nice and safe with the accompanied Stewart pressed safety latch. Conveniently, this has adjustable stops to make you look like you get it perfect every time.

Summary

TRC Tractors has a reputation around the Manawatu for taking its customers’ needs to the next level (the pimp my ride TRC edition tractors create a little bit of a head-turning point for customers). They are also willing to go directly to the factory and say, ‘hey these are some things that in New Zealand we feel could be a great advantage’. And with a company like Stewart being on-board, ready and willing to listen, results like the NZ5500 happen.

This is an elite end product – the flexi paint has a beautiful finish, and the New Zealand and Scottish flags is a nice touch, perfectly summing up what is sure to be a long-lasting alliance.

Stewart Trailer NZ5500 specifications

Deck length	5.5m
Deck Width	2.7m
Axle	Commercial 10 stud
Tyres	560/60R 22.5
Body	Removeable silage bin and gravel sides

Pros 

• Ultimate all-rounder
• Durable flexi paint
• Hardox deck and gravel sides
• Well manufactured and presented machine
• High-speed 10-stud commercial axles and brakes
• Low centre of gravity
• High rolling circumference tyres make them easy to pull and reduce ground compaction
• Exceptionally smooth trailer to pull, no shunting, or swaying even at 55km fully loaded.
• Felt stable tipping on the silage stack
• Central grease bank

Cons

• Roll-on/roll-off makes shipping more expensive, but you will get the machine quicker and with soaring container prices; additional cost could become negligible 

Find new and used farm machinery for sale in NZ 

Photography: Jaiden Drought