How much can your car actually tow?
The trailer is only half the equation. Your car, its tow bar, the ball and the coupling each carry their own rating, and the lowest of them is your real limit. Buying a trailer your vehicle cannot legally pull is an expensive mistake, and an easy one to make.
Braked and unbraked ratings are different
Vehicle handbooks quote two towing capacities. The unbraked figure is the lower of the two and is what applies to a trailer with no brakes of its own. Check which one you are reading before you commit to a trailer size — the gap between them is usually large.
The tow bar has its own rating
A tow bar is separately rated for both towing capacity and maximum ball weight, and it can be lower than the vehicle’s. So can the tow ball and the coupling. The weakest link in the chain sets the limit, no matter what the vehicle is capable of.
GCM caps the whole lot
Gross Combination Mass is the maximum for the loaded car and loaded trailer together. It is entirely possible to be under your towing capacity and over GCM at the same time, particularly with passengers, a full tank and a loaded ute tray.
Brakes become mandatory as weight climbs
Australian law requires braking on heavier trailers, with a further step up — including a breakaway system that applies the brakes if the trailer separates — once you get heavier again. Anything built to order should be specified with this in mind from the outset.
Loading and driving, once you are legal
Load over the axle, slightly forward
Weight too far back lightens the ball and starts sway; too far forward overloads the ball and lifts the tow vehicle’s front. Aim for about ten per cent of the loaded weight on the ball and keep heavy items low.
Sway starts as a wobble
It builds, it does not appear. Ease off the accelerator rather than braking hard or steering out of it, and check the load distribution at the next safe stop rather than pressing on.
Everything takes longer
Braking distance, overtaking, and getting up to speed. On the Kings Highway and the Clyde, engine braking on the descent saves your brakes far more than riding the pedal does.
Check the coupling every time
Latched, pinned, safety chains crossed and rated, and the plug seated. A quick walk around before every trip catches nearly everything that goes wrong.
Tyres are a load rating, not just a size
Trailer tyres carry a load rating and age out even with plenty of tread left. A cheap tyre on a heavy trailer is a poor economy — the spare counts too.
Brakes need servicing
Electric brakes need their magnets, wiring and controller checked, and the shoes wear like any other. See servicing and repairs.
Keep reading
Ask about a build, a repair or a service
Tell us what you need to carry and we will come back with what suits it and what it costs. Enquiries go straight to the Resort Trailers workshop in Queanbeyan — no call centre, no obligation.