Caravan and Trailer Braking Systems

So, you have made your big purchase and secured your dream caravan, camper or trailer. But now you need to know how to safely navigate the roadways of Australia with it. Stopping safely is a big part of driving your vehicle around regardless of what you are towing. A big part of towing a caravan or trailer safely is ensuring that the braking systems are adequate.

The Australian Design Rules (ADRs) are our national standards for road vehicle safety, anti-theft and emissions. All new road vehicles manufactured in Australia and imported new or second-hand vehicles, must comply with the relevant ADRs when they are first supplied to the Australian market.

When a vehicle is first used on an Australian road, the relevant state or territory government legislation generally requires that it complies with the relevant ADRs as at the time of manufacture.

According to the Australian Design Rules, all trailers over 750kgs GTM (irrespective of the towing capacity or unladen mass of the tow vehicle) must have an effective brake system fitted.

All brakes must be operable from the driver’s seat of the tow vehicle except for over-ride brakes. The minimum braking system required for a trailer or caravan depends on its type and weight, as well as the weight of the tow vehicle:

  • Up to 750kgs GTM: No brakes are required.
  • 751-2,000kgs GTM: There must be a braking system on the wheels of at least one axle and over-ride brakes are permitted.
  • Over 2,000kgs GTM: A brake system operating on all wheels is required. The system must be capable of automatically activating should the trailer become detached from the tow vehicle. Under these circumstances the brakes must remain applied for at least 15 minutes. These ‘break-away’ systems are compulsory on all trailers over 2,000kgs GTM.
  • The cable which attaches the break away system of the trailer to the tow vehicle must be connected/attached to a substantial portion of the tow vehicle.

Override brakes
Mechanical override brakes use the tow coupling to manually pull a cable connected to the trailer’s brake drums. These are permitted when the GTM is under 2000kg.

Electronic brakes
They are automatically applied by the brake controller and can be manually operated by a manual control which is installed within reach of the driver. Electronic brakes are most commonly used on caravans and trailers over 750kg and are legally required on all caravans and trailers where the GTM is more than 2000kg. Remember that if you are considering electronic brakes, you will need to install a control unit either in the tow vehicle or on the caravan/trailer.

Breakaway systems
These systems provide a way of automatically turning your caravan’s electronic brakes on in an emergency. If you caravan was to become uncoupled from the tow vehicle, a battery will keep the system operable on the caravan for at least 15 minutes. All states require that caravans and trailers with a GTM of more than 2000kg to have this system.

The weight of your caravan will also determine the number and type of safety chains required while towing:

Trailers that do not exceed an aggregate trailer mass (ATM) of 2500kg must have at least one safety chain fitted.

Trailers more than 2500kg and not exceeding 3500kg ATM must have two safety chains of 3500kg designation fitted.

Trailers more than 3500kg ATM must have two safety chains made from steel of a minimum 800MPa breaking stress. Each chain must be sized such that the minimum breaking load exceeds the ATM.

In some states there may be additional requirements that require an indicator light or audible signal showing the battery on board the caravan is sufficiently charged to enable the battery to satisfactorily activate the brakes, via the break-away system, on all wheels should the trailer detach from the tow vehicle. This indicator light must be visible or heard from the driver’s seated position and must operate only while the ignition is in the “engine on” position or whilst the engine is running. Contact your State or Territory roads and traffic authority regarding the requirement of a visible or audible indicator with your ‘breakaway’ system.

When used and adjusted properly your braking system should provide many kilometres of smooth, dependable braking operation. It is important that the performance of the brakes on both the towing vehicle and the trailer are balanced so that neither are overloaded. If the correct balance is not obtained between the braking systems, then overheating of either system may occur with a deterioration in brake performance.

Correct brake balance is obtained when the trailer brakes have a slight lead over the brakes on the towing vehicle. This can be accomplished by the adjustment of the controller in the towing vehicle. When correctly adjusted there will be no sensation of the trailer pushing the vehicle, nor any excessive pull during braking.

Depending on your braking system type - visit the Fineline Trailers website where you will find more technical information on the different types of braking systems. You can also purchase braking consumables and electric control modules through our online store


AL-KO Electric Brake Handbook


Mechanical Brake – Adjustment Instructions


Mechanical Drum Brakes – Instructions For Replacing Brake Shoes


AL-KO 9” Hydraulic Brakes – Adjustment Instructions



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