Trailers, towing and cargo

Rules and facts regarding trailers

• A trailer changes the grip your car's tyres have on the road, you should be aware of that. When the load in a trailer is all the way in the front it causes a high ball pressure, meaning that the back of the car is being pressed down and the front of the car is elevated, shown by image A (image 1). This can cause oncoming traffic being dazzled by your car's headlights. Image B shows a low ball pressure, where the back of the car is elevated instead and the front of the car is pressed down.

Image 1: High vs low ball pressure

• A ’towed vehicle’ specifically refers to a vehicle that is connected to your car, but which is not a trailer. So a trailer is not classified as a towed vehicle.
• When it comes to winter tyres on a trailer, the only rule to keep in mind is that if the car has studded tyres, then the trailer must have studded tyres as well. But if you want to drive with a trailer that has studded tyres, then it doesn’t matter whether your car has either studded or non-studded tyres. If the car has non-studded tyres then the trailer can have either studded (during winter) or non-studded tyres. Simplified it looks like this;

-          Car non-studded + Trailer non-studded = Okay

-          Car non-studded + Trailer studded = Okay

-          Car studded + Trailer studded = Okay

-          Car studded + Trailer non-studded = Not okay

• With only a B driving licence you may drive with either; 1) a light trailer, which has a total weight of maximum 750 kg, or; 2) a trailer more than 750 kg, but where the combined total weight of the car and trailer is maximum 3.5 tonnes.

This means that with a normal B driving licence you’re only allowed to drive light trailers. A trailer is considered to be light if the total weight is not higher than 750 kg. However, this also means that a trailer that is heavier than 750 kg can also be considered light, if the total weight of the car and the trailer is not higher than 3500 kg (3.5 tonnes).

• If you’re driving with an unbraked trailer that has a total weight (or, in case the trailer has no load; the kerb weight) which is higher than half of the kerb weight (also known as unladen weight) of your car, then the maximum speed you’re allowed to drive is 40 km/h.

Rules regarding towing another car with your car

• If the distance between the towing car and the towed car is greater that 2 metres, then the  tow line has to be marked.
• Towing another car on a motorway can de very dangerous, therefore you’re allowed to tow another car only to the nearest exit. Also, on motorways you must  keep yourself and the towed car on the hard shoulder, or if there isn't any hard shoulder, as far to the right side of the road as possible.
• The lights of the car that is being towed must be on. However, if they don't work, then you have to mark the car to increase its visibility in darkness and fog.

Rules and permissions regarding towing

• With a B driving licence you may pull a light trailer, and these come in both braked and unbraked versions, this means that you’re allowed to pull each version of light trailers.
• If you quickly need to find out which categories someone is allowed to pull or not, then it’s sufficient to take a look at his or her driving licence.
• The maximum speed when driving with a caravan is 80 km/h due to a caravan being so big. It makes stopping distances longer and in general it will be lot more dangerous if you would be driving fast.
• A motorcycle isn't allowed to be towed att all due to how delicate these have been build, towing it could lead to serious damages which could make driving it dangerous.
• The maximum length a combination of a vehicle and trailer is allowed to be is max 24.0 metres including load, and 25.25 metres in certain cases.

In ’certain cases’ means that there are specific conditions for which the vehicle/trailer combination is allowed to be up to 25.25 metres. One of these specific conditions is that every vehicle in this combination is equipped with antilock brakes and coupling devices which are prescribed by the Swedish Transport Agency. But in general the anwser is that the max permitted length is 24.0 metres if nothing specifically is stated.

• A towed vehicle is not the same as a trailer. Towed vehicles are for example class I heavy equipments or other motor vehicles that are being towed. The max allowed speed to drive with these is 30 km/h. However; If the wheels of that which you’re towing are made of hard material, for example steel or iron, then the maximum permitted speed to drive is 10 km/h.

Cargo and load

• Whether the cargo is located inside or outside the car does not matter, both their weight is included in the cargo weight. Keep in mind that the passengers weight is also counted as cargo weight.
• Load that protrudes more that 1 metre in either the front or back side of the car should be marked with a flag during daytime on the protruding side(s).

When it’s dark; if the front side protrudes it has to marked with a white light and white reflectors, if the back side protrudes it has to be marked with a red light and red reflectors.

• When transporting cargo with a trailer, the following rules apply about how much pressure the fastenings should at least be able to withstand, as compared to the weight of the load itself; on the sides and in the back 50%, in the front 80%.
• Keep in mind that the cargo is not included in the car’s kerb weight. The car's kerb weight (also known as unladen weight) is the overall weight according to the certificate of registration in fully operational condition and the weight of the driver. The kerb weight also includes the spare wheel, tools that belong to the vehicle, fuel, water and oil. But this does not include any load.
• A private car may only be driven on a public road if the width of the car, inluding cargo, is not more than 260 cm, and the cargo does not project more than 20 cm on the sides of the car. So in this case (image 2), car A is not allowed to be driven on a public road although it’s only 250 cm wide, but car B is allowed.

Image 2: Examples of different widths, A is not allowed on public roads