A vehicle’s categorisation under the Australian Design Rules can affect what modifications are allowed on it, based on the National Code of Practice for Light Vehicle Construction and Modification (VSB 14)
New vehicles in Australia are classified under a handful of different categories: Two and three-wheeled vehicles (L), Passenger vehicles (M), Goods vehicles (N), and Trailers (T).
What we are worried about in this instance are passenger vehicles. Vehicles in the passenger category break down further into sub-categories; there are ones that pertain to small buses and other people carriers, but the two that we want to focus on is MA and MC classification:
4.3.1. MA Passenger Car: A passenger vehicle, not being an off-road passenger vehicle or a forward-control passenger vehicle, having up to 9 seating positions, including that of the driver.
4.3.3. MC OFF-ROAD Passenger Vehicle: A passenger vehicle having up to 9 seating positions, including that of the driver and being designed with special features for off-road operation.
Dig a bit deeper, and the MC classification also has a few other guidelines that define ‘special features for off-road use’.
(a) Unless otherwise ‘Approved’ has 4 wheel drive; and
(b) has at least 4 of the following 5 characteristics calculated when the vehicle is at its ‘Unladen Mass‘ on a level surface, with the front wheels parallel to the vehicle’s longitudinal centreline, and the tyres inflated to the ‘Manufacturer‘s’ recommended pressure:
(i) ‘Approach Angle‘ of not less than 28 degrees;
(ii) ‘Breakover Angle‘ of not less than 14 degrees;
(iii) ‘Departure Angle‘ of not less than 20 degrees;
(iv) ‘Running Clearance‘ of not less than 200 mm;
(v) ‘Front Axle Clearance‘, ‘Rear Axle Clearance‘ or ‘Suspension Clearance‘ of not less than 175 mm each.
So, in other words, the vehicle needs the basic tenants of a 4X4 intact: Drive to all four wheels and decent ground clearance for the body and driveline. It’s all fairly academic if you look at it from a point of view of when you are deciding what modifications you want to make to improve say the Adventra’s off-road capability our modified Adventra technical passes 4 out of 5 of these MC requirements.
What changes can actually be made to an MC vehicle over an MA vehicle? That depends. Each state has a set of views on modifications, but generally, the rules follow a set of standards and guidelines, a couple of which are highlighted below (note these may vary between states, so always need to be checked):
- The diameter of any tyre fitted can be up to 50mm larger or more than 26mm smaller
- Up to 75mm of total lift, tyres and suspension or 1/3 of suspension travel and restrictions on tyre diameter
These two alone affect somebody looking to make proper modifications to their four-wheel drive and could make or break the purchase decision between an Everest and one of its MC-classed competitors. Making these modifications to an MA vehicle could be against the law and could void insurance in some instances, so it’s always worth checking.
So, just to be clear, the MA classification does not prevent a vehicle from being used as a four-wheel drive or as a heavy off-road vehicle, it simply prevented certain modifications from being made to the vehicle that would be accepted under the Australian Design Rules.