Whether you’re towing a caravan, camper, or trailer, understanding the towing capacity of your vehicle and the Aggregate Trailer Mass (ATM) of your trailer is essential for safe and legal towing. In this guide, we’ll explain what towing capacity and ATM mean, how to calculate them, and why they’re crucial when choosing the right OzHitch coupling for your setup.
What is Towing Capacity?
Towing capacity refers to the maximum weight that your vehicle can safely tow. This includes the weight of your trailer and all its contents. Exceeding the towing capacity can lead to unsafe towing conditions, damage to your vehicle, and potential legal issues.
Types of Towing Capacity:
- Braked Towing Capacity: This is the maximum weight your vehicle can tow when the trailer is equipped with its own braking system, like electric or override brakes.
- Example: Your vehicle might have a braked towing capacity of 3,500kg.
- Unbraked Towing Capacity: This refers to the maximum weight your vehicle can tow when the trailer doesn’t have its own brakes.
- Example: Your vehicle might have an unbraked towing capacity of 750kg.
What is ATM (Aggregate Trailer Mass)?
Aggregate Trailer Mass (ATM) is the total weight of your trailer when fully loaded, including all cargo, fuel, water, and accessories. This figure is vital because it helps determine if your trailer is within the legal and safe limits for towing with your vehicle.
How to Find Your ATM:
The ATM is usually listed on the trailer’s compliance plate, or you can calculate it by weighing your fully loaded trailer at a weighbridge.
Why ATM Matters:
The ATM helps you determine the correct OzHitch coupling and whether your vehicle can legally and safely tow your trailer. For example, a trailer with an ATM of 2,500kg would require an OzHitch model rated for at least 2.5 tonnes, and your vehicle must have a towing capacity equal to or greater than the trailer’s ATM.
How to Calculate Towing Capacity and ATM Compatibility
- Check Your Vehicle’s Towing Capacity: This information is usually found in the vehicle owner’s manual or on the manufacturer’s website. Look for the braked towing capacity if your trailer has brakes, or the unbraked towing capacity if it does not.
- Determine Your Trailer’s ATM: The ATM is the maximum weight your trailer can be when fully loaded. Make sure this number doesn’t exceed your vehicle’s towing capacity.
- Match with the Correct OzHitch Model:
- For a trailer with an ATM of 2.0 tonnes or less, the OzHitch 2.0T coupling is suitable.
- For a trailer with an ATM of up to 2.5 tonnes, choose the OzHitch 2.5T coupling.
- For heavier trailers up to 3.5 tonnes (ATM), the OzHitch 3.5T coupling is the best choice.
Gross Trailer Mass (GTM) vs. ATM
Another term you might encounter is Gross Trailer Mass (GTM), which is the weight of the trailer when it’s fully loaded and hitched to the towing vehicle. GTM is always lower than ATM because part of the trailer’s weight is transferred to the vehicle’s towball.
For towing safety, both GTM and ATM are important to consider, but ATM ensures you do not exceed the maximum weight your trailer can be when fully loaded.
Why Towing Capacity and ATM are Important
Understanding towing capacity and ATM helps you ensure that your vehicle and trailer are within safe, legal limits. Overloading your vehicle or using an inappropriate coupling for the weight can lead to:
- Loss of control while towing.
- Increased wear on your vehicle and towing components.
- Legal fines or penalties for exceeding weight limits.
Choosing the right OzHitch coupling for your setup, based on towing capacity and ATM, ensures safe towing and reliable performance, even on rough off-road conditions.
How OzHitch Couplings Can Help
OzHitch offers a range of couplings designed to suit different towing capacities and trailers with various ATM ratings. With options available for unbraked, override brakes, and electric brakes, OzHitch ensures you can find the perfect coupling for your towing setup.
- OzHitch 2.0T Coupling: Suitable for override braked trailers with an ATM of up to 2,000kg.
- OzHitch 2.5T Coupling: Ideal for unbraked or electric braked trailers with an ATM of up to 2,500kg.
- OzHitch 3.5T Coupling: Best for heavy-duty off-road trailers with electric brakes and an ATM of up to 3,500kg.
For more detailed information on each model and compatibility, visit our Product Page.
Need Assistance? Contact Us!
If you have any questions or need further assistance, feel free to call us on (08) 8260 2277 or Contact Us here. We’re here to help ensure your OzHitch coupling is always performing at its best.
For more installation resources and tips, visit our Resources Page.
OzHitch: Built for the toughest conditions, engineered for safe towing.