Horse trailer safety: safe travels

July 16, 2018

Transporting your horse can be a stressful experience, but ensuring your trailer is road worthy and safe will help journeys fly by. 

During the course of the year, we see many horse trailers that shouldn’t be on the road. Such trailers are used to carry very expensive horses, someone’s real pride and joy, but in fact, the trailers really need attention, and in some cases urgently.

Learning from experience

We hear of cases where horse trailers are being borrowed, rented or are out on long term loan from the owners, but were never safety checked beforehand, making it a very dangerous practice. Will the borrower have the correct BE prefix on their licence to be able to tow if they passed their car driving test after 1st January 1997 (before that date they have grandfather rights), have they got the correct insurance and above all are they skilled in using the trailer and able to reverse safely and accurately?

People should never underestimate the importance of travelling horses safely and securely. A horse should always travel with protective gear, including leg protectors and a leather head collar (as these break far easier than nylon head collars, vital in an emergency), and bedding should be put down to prevent the horse slipping on floor.

Another vital lesson comes to the issue of weight. As lovely as horses are, they are also very heavy and it is important that weights are checked, making sure weights of the horse or horses do not exceed the towing limit for the tow vehicle. Also, when travelling with just one horse, load it on the offside in the box to help the stability of the tow vehicle and adapt to the camber of the road.

Bedding should be used to stop the horse slipping, but needs thorough cleaning as urine can cause havoc to the floor

Hitching up

When it comes to hitching the trailer to the tow vehicle, line up the towball and secure the breakaway cable, so if you need to release the handbrake to slowly move the trailer, the cable is already there to secure any movement. Always check the jockey wheel is in good condition before going anywhere. Once the trailer coupling is fitted on the towball, make a couple of turns back up using jockey wheel. This won’t cause any undue wear and is a very important step to remember as it shows whether or not the coupling is raising on the tow vehicle, as well as if it is locked and fitted correctly.

A very important factor to take into consideration is the fitting of the breakaway cable. The cable must be fitted to the towbar by using a dedicated recess, and not fitted around the towball itself as if there was a problem during travelling causing the coupling to lift off the towbar, the cable would fly off and a major accident would develop. The purpose of the breakaway cable being connected to the brake assembly is to activate the trailer brakes, and it is a legal requirement.

Looking at the coupling, the main assembly to hitch to the vehicle, there should never be any up and down movement. Keep it well greased to reduce wear and monitor the level of wear as there should never be any more than 3mm wear when secured on the towball.

It is always a good idea to carry a spare breakaway cable! We have known a case where one was stolen from a trailer, causing the owner to travel home without one -be mindful as this is a legal item.


Make sure all lights are working correctly, both on the trailer and the tow vehicle. No matter how small a crack may be on the light lens water will soon find its way in, and as light connections can be very small and flimsy, they will soon rust. If there are any signs of both indicator and side lights starting to flash and dim together, is time to get wiring checked as this may be a possible earthing problem. Don’t forget make sure any front marker lights are also working, as these are particularly helpful for oncoming driver the gauge the width of your trailer. With the introduction of LED lights, it is worth thinking about upgrading, as LEDs are brighter than halogen headlights while still offering a warm light.

Make sure the number plate light is in good order and working. Plus double check you have the correct number plate fitted to match tow vehicle!


It is vital that all tyres on tow vehicle and trailer are in good order and riding with the correct pressures. Tyres will deteriorate over time, especially where trailers and horse boxes sit for weeks not being used. If cracks start to appear, it is an indication that the rubber is drying out and starting to deteriorate. Tyres will always last longer if inflated to the correct pressure, and don’t forget to keep check on the spare wheel and check wheel nuts.

The law states that tyres can have a minimum of 1.6 mm of tread over 75 per cent of the tread width, but be aware that trailer tyres can perish long before the tread wears out. Keep a look for sidewall cracking and any bulges, which are caused by air getting between layers of a damaged tyre or cuts within the reinforcing which could cause a tyre to blow out.

Make sure you fit tyres with the correct weight rating and invest in top quality tyres, as your horse and trailer are both major investments so it makes sense to make sure they have the best!


Again with trailers standing for long periods, brake assemblies can rust up. To minimise this, chock under the wheels and park with the handbrake in the off position. If you experience any sign of the handbrake getting stiff to use, get it checked by a dealer straight away. Brake shoes can rust and the linings can break away from the metal shoe in time, so its better to be on the safe side.

It is vital all lights are working and replaced when damaged

There are many parts to the cables and rods underneath that need greasing and attention so regular servicing is a must. Brake adjustment ought to be made every 2000 mile or sooner, which is the same for coupling hitch overrun. Unless fitted with seal for life wheel bearings, we recommend trailer wheel bearings are greased within 18 months but this is heavily dictated by the amount of use. Always make sure hub bearing caps are fitted to save dirt and water getting into the wheel bearings.

Keeping it clean

Horse trailers really do need to be kept clean and in tip top condition. Many horseboxes tend to suffer with decay and rot on the lower edges of trailer sides and ramps, so keep an eye on this with regular cleaning. It is vital to keep check under floor matting or if your box is fitted with wood flooring, check the floor panels very regularly.

Don’t forget that at this time of year if you are washing down inside, make sure rubber mats are dry before putting them back as any wet during winter could cause the box to ice up along with a whole host of other problems.

Your responsibility

At the present time, there is no MOT Test for trailers therefore it is your duty to make sure your trailer is road worthy and in order for any insurance liability. However, towbars on vehicles are checked, so if you have a detachable towball on your tow vehicle, make sure it is fitted when your car is going through its MOT.

Make sure towbar nose weight is correct as if the pressure is too high, it with effect the tow vehicle suspension and in turn affects steering.

Keeping your trailer in the best condition will put your mind at ease and make sure you get to your destination calmly and ready for what’s in store!