Arctic Trucks in Australia: big tyres, five practical questions

Big tyres have an immediate appeal. They change the proportions of a fourby and invite thoughts of tracks that usually demand a careful line. Arctic Trucks’ Australian presence gives that interest a more substantial starting point: locally marketed vehicle conversions, with Marks 4WD behind the Australian operation. The range includes the Isuzu D-Max AT35 and Toyota LandCruiser Prado 250 AT37. Arctic Trucks Australia

The D-Max package combines 35-inch tyres with changes to the body and frame, Bilstein suspension and speedometer recalibration. The Australian Prado listing goes further in tyre size, specifying 37-inch BFGoodrich KM3s, forged 17-inch wheels and adjustable R53 suspension, alongside wider bodywork and system recalibration. These are integrated conversions with work extending well beyond fitting larger rubber. D-Max AT35 specification, Prado AT37 specification

The nominal step from a 35-inch tyre to a 37 increases its radius by one inch: 25.4 mm. That gives some scale to the extra rubber. It is a geometric comparison, not a measured clearance gain: actual tyre dimensions, deflection under load and the component being measured all matter. It also cannot tell us how much more clearance the Prado has than the D-Max, because the vehicles and conversions differ. BFGoodrich itself cautions that published tyre dimensions can vary. BFGoodrich KM3 dimension notes

That makes the complete conversion worth examining. Here are five ownership questions behind the tyre size.

First, what exactly will be delivered? Request a written Australian specification tied to the vehicle being purchased: tyre model, wheel size, suspension, fitted accessories and warranty responsibilities. Discuss who looks after the base vehicle and who handles the conversion, including the process if a fault involves both. Keep the final specification with the service records.

Second, what paperwork covers that vehicle? Arctic Trucks’ Australian website promotes Australian compliance. Our research has not independently established the approval details for every model, variant and registration pathway. Ask the supplier for the documents applicable to the proposed vehicle, including the scope of its approval, and confirm the registration and insurance arrangements before committing. The paperwork needs to cover your exact vehicle and conversion. Arctic Trucks Australia’s compliance statement

Third, where does the spare live? The Australian Prado page says its standard spare is removed during conversion. That makes a matching spare, its mounting position and the means to handle it part of the buying discussion. A spare carried inside competes with camping storage; an external carrier becomes part of the weight, rear-access and parking plan. Sketch the finished layout before choosing drawers and a fridge. For either vehicle, include spare-wheel storage in the written specification. Prado AT37 conversion notes

From Josh’s Great Central Road experience: I have driven its corrugations in a HiLux with stiffened springs and close to a tonne in the tray. For that sort of trip, I would want a usable spare and another person who could help with a wheel change. Conditions and access advice matter too. That experience is one reason I would settle the spare-wheel arrangement before choosing a big-tyre touring build.

Fourth, how will replacement tyres be obtained? Before an extended trip, call tyre suppliers along the planned route with the exact size and load specification. Ask whether they stock it, how long ordering takes and what recovery or freight options exist if they cannot. This is a planning exercise; a tyre being available through a national supplier does not tell you what a particular town has on the shelf that day.

Fifth, what remains when the touring gear is aboard? Ask for the completed vehicle’s measured weight and documented mass limits, then build the trip load around those figures. Put passengers, water, camping equipment, accessories and any trailer coupling load into the same conversation. Request a test drive representative of your use and pay attention to access, parking, steering feel and the ease of living with the finished vehicle.

Josh's take: Big-tyre conversions have their place. For an occasional weekend away or one major trip a year, I would find it harder to justify the spend unless the extra capability solved a problem I actually had. My concerns would be the everyday ride, steering feel, fuel consumption and road noise. Those are things I would want to assess in the finished vehicle before buying.

A second wheel-and-tyre set might appeal to some owners, but I would also count the cost, the changeovers and somewhere to store it. For me, the practical question is how much use the extra capability will get across a whole year.

That perspective is a buying brief, not a road-test verdict. Arctic Trucks changes the suspension and other components as part of these packages, so we cannot assign a measured change in comfort, steering or consumption from tyre size alone. D-Max conversion specification, Prado conversion specification

Before choosing one, draw the touring load around a matching spare, measure the places the finished vehicle needs to fit and check tyre support along the route. The conversion should earn its place in that plan.