Safety Considerations When Towing a Horse Float

Written by Michelle Bassola

Understanding Trailer Weight and Towing Capacity

Towing a horse float is a specialised task that combines vehicle dynamics, trailer engineering, and animal welfare. Unlike standard cargo, horses are live loads that shift their weight during transport, which can significantly affect vehicle handling. For this reason, understanding trailer weight, towing capacity, and load distribution is critical.

Choosing the Right Tow Vehicle

The tow vehicle must be capable of safely handling the combined weight of the horse float, horses, tack, and supplies.

Key Vehicle Requirements

• Adequate towing capacity as specified by the vehicle manufacturer

• Suitable tow bar and hitch rating

• Electric brake controller

• Good suspension and tyres

A horse float carrying two horses can weigh well over 2,500 kg. Exceeding the vehicle's towing limit can reduce braking performance, increase sway, and place excessive stress on the engine and transmission, as well as jeopardising insurance coverage in the event of an accident.

Understanding Weight Terminology

Before towing, drivers should understand the technical terms used by manufacturers and regulators.

Tare Mass

The empty weight of the horse float with no horses, tack, feed, or water onboard.

Gross Trailer Mass (GTM)

The maximum allowable weight supported by the trailer's wheels when coupled to the tow vehicle.

Aggregate Trailer Mass (ATM)

The total maximum weight of the loaded trailer, including the portion imposed on the tow ball.

Tow Ball Download (TBD)

The vertical force exerted by the trailer coupling onto the tow vehicle's tow ball.

Gross Combination Mass (GCM)

The maximum legal weight of the fully loaded tow vehicle and fully loaded trailer combined.

Gross Vehicle Mass (GVM)

The maximum permissible weight of the tow vehicle itself, including passengers, fuel, and cargo.

How These Figures Relate

The following relationship applies:

ATM = GTM + TBD

Example

• Loaded horse float weight (ATM): 3,000 kg

• Tow ball download (TBD): 300 kg

• Weight on trailer axles (GTM): 2,700 kg

Calculating Actual Trailer Weight

Example

• Empty float: 1,700 kg

• Two horses at 550 kg each: 1,100 kg

• Tack and supplies: 200 kg

Calculation:

1,700 + 1,100 + 200 = 3,000 kg

The loaded trailer ATM is 3,000 kg.

Consequences of Overloading

Overloading your vehicle's towing capacity is both dangerous and illegal. It compromises your steering and braking power, placing extreme strain on your engine and transmission. Worse still, exceeding safe weight limits can cause serious accidents, lead to heavy fines, and result in insurance claims being completely voided.

Causes of Trailer Sway

• Excessive speed

• Poor weight distribution

• Strong crosswinds

• Underinflated tyres

• Steering corrections that are too abrupt

What to Do if Sway Occurs

• Keep the steering wheel straight.

• Ease off the accelerator.

• Apply the trailer brakes manually, if fitted.

• Do not brake hard with the vehicle brakes.

• Once the sway stops, pull over and inspect the load and tyre pressures.

Recommended Safety Margins

Suggested safety margins include:

• Use no more than 85–90% of the vehicle's rated towing capacity.

• Keep GVM and GCM below their maximum values.

• Verify tow ball load using a scale.

• Weigh the complete vehicle and trailer combination at a public weighbridge.

A float that is technically legal may still be difficult to tow if the vehicle is operating at its limits.

Example of a common towing combination: