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What You Need to Know About Heavy Vehicles

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If you own a heavy vehicle for personal or business purposes, it’s important to understand the relevant safety standards and regulations. According to the National Heavy Vehicle Regulator (NHVR) in Australia, all vehicles with a Gross Vehicle Mass (GVM) or an Aggregate Trailer Mass (ATM) of 4.5 tonnes or more are considered heavy vehicles. All heavy vehicles in Australia must comply with the Heavy Vehicle National Regulation (Vehicle Standards) in order to be considered roadworthy.

In this blog, we will cover what’s involved in NHVR inspections. For business owners, we will also discuss the benefits of fleet maintenance. Having a solid understanding of heavy vehicle standards and maintenance can reduce vehicle downtime and could even save you from legal trouble.

If you have further questions about your heavy vehicle, we recommend consulting your local truck mechanic.

National Heavy Vehicle Inspection Manual

The National Heavy Vehicle Inspection Manual aims to provide vehicle owners and drivers with a standardised checklist for roadworthiness. Adhering to this manual will reduce the risk of your heavy vehicle breaking down in the future. It also reduces the chances of accidents occurring on the road. For business owners, this ultimately means less downtime for your fleet. As such, it is vital that you understand the contents of this manual.

The following is a simplified summary of the Inspection Manual. We recommend that you also have a read of the full manual on the official NHVR website.

The Vehicle Identification Number (VIN) is said to be the fingerprint of a heavy vehicle. This allows the inspectors to verify the authenticity of the vehicle. It also helps them distinguish one vehicle from another. This is particularly important in the context of fleet management.

Vehicle Identification

Your vehicle won’t be able to pass this criterion if:

  • There is no VIN plate or chassis number
  • The VIN number differs from the chassis number
  • The VIN number has been altered
  • The engine number has been altered or is missing.

Inspection Checklist

This part of the manual outlines all the safety, mechanical and electrical parts that need to be inspected. All these components need to be in working order to ensure the safety and longevity of your heavy vehicle.

According to the manual, the following parts will need to be inspected:

  • Brakes
  • Couplings
  • Steering and suspension systems
  • Wheels, tyres and hubs
  • Structure and body condition
  • Seats and seatbelts
  • Lights and reflections
  • Mirrors
  • Windscreens and windows
  • Engine and exhaust

The inspection must be carried out by a qualified inspector. According to VicRoads, heavy safety and compliance services are conducted by NHVR Safety and Compliance Officers (SCO). The Inspection Checklist must be completed with the inspector’s name and signature on the form. Additionally, there is a separate checklist for attached trailers that also needs to be completed by an authorised officer 

To inspect and approve any modifications made to heavy vehicles, NHVR will provide Approved Vehicle Examiners (AVE).

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Trailers have a similar inspection list to the vehicle itself. They need to have the proper identification number, wheels, tyles, brakes, lights and so on. However, there are several parts that are specific to the trailer.

For example, the towing attachment must be in working condition. Your vehicle will fail this criterion if:

  • The towing attachment is loose, cracked, corroded or broken
  • The coupling locking device is broken
  • The rear overhang exceeds 30% of the distance from the point of articulation to the centre of the rear overhang line

If you have an advanced braking system for your trailer, make sure that it doesn’t come into contact with moving parts or high temperatures. Additionally, make sure that no electrical wiring is exposed. Always keep an eye on the warning lamp as it will indicate if there’s any faults with your braking system.

Vehicle Dimensions

In terms of the vehicle dimensions, the restrictions might differ depending on the type of heavy vehicle that you have. Here are the restrictions on vehicle dimensions according to the NHVR:

  • Height

Double deck bus – The height must not exceed 4.4 metres.

Livestock carriers, vehicle carriers or semi-trailers – The height must be 4.6 metres or less.

  • Width

For all heavy vehicles, the width must not exceed 2.5 metres. This measurement excludes anti-skid devices, mirrors, signalling devices and tyre pressure gauges.

  • Overhang 

The rear overhang is measured from the rear overhang line to the end of the vehicle. This measurement must include any sort of cargo. Please see the full manual (Section 16) for a diagram that shows this measurement.

As per the NHVR, the overhang restrictions for various heavy vehicles/trailers are as follows:

Heavy motor vehicle – Must not exceed 60% of the distance from the front of the axle to the rear overhang line, or 3.7 meters (whichever is lesser)

Dog trailer -Must not exceed the distance between the front of trailer body to the rear overhang line, or 3.7 metres (whichever is lesser)

Pig trailer -Must not exceed 60% of the distance from the articulation point to the rear overhand line, or 3.7 meters (whichever is lesser)

Additional Criteria

This manual is relevant to all participating states and territories. However, there are additional criteria for those in Queensland, South Australia and Tasmania. Please refer to the NHVR website if you own a heavy vehicle in these states.

Fleet Services

If you run a business with a fleet of heavy vehicles, it’s going to be difficult to keep track of each vehicle. Because of this, you should consider hiring fleet service mechanics. Fleet mechanics have a solid understanding of the NHVR standards and will make sure all your vehicles pass the inspection.

Fleet mechanics will conduct maintenance and repairs on all your vehicles. They can also help you with fleet selection and analysis. This will help you optimize your fleet by making sure that you’re using the most fuel-efficient vehicles for your particular type of business. Fleet services also cover registrations and licensing.

When choosing a fleet service provider, it’s a good idea to look for one that specialises in heavy vehicles like trucks and buses.

That was just a brief summary of what you need to know about heavy vehicles. Once again, we recommended reading through the NHVR manual yourself and consulting your local truck mechanic. It’s important to meet the criteria in order to keep yourself and other motorists safe. At the very least, it’s going to ensure that your heavy vehicle lasts for as long as it can.

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