Weights & Dimensions

• The maximum individual truck length is 12 metres
• Articulated truck and trailer length is 16.5 metres and road trains are allowed up to 18.75 metres.
• The maximum width is 2.55 metres or 2.60 metres for refrigerated lorries If a vehicle has an overall height of 3 metres or above, a sign must be displayed in the cab showing its full height.

All vehicles over with a maximum authorised mass over 7.5 tonnes must have markings on the rear of the vehicle. These markings are rectangular and are coloured red and yellow.

Vehicle categories on driving licences can depend on the vehicle’s weight – the different terms you may see are explained below.

The unladen weight of any vehicle is the vehicle’s weight when it’s not carrying any passengers, goods or other items.

It includes the body and all parts usually used with the vehicle or trailer when used on the road. It doesn’t include the weight of the fuel or if it’s an electric vehicle, the batteries.

Kerbside weight is similar but includes a tank of fuel.

Maximum authorised mass (MAM) means the weight of a vehicle or trailer including the maximum load that can be carried safely when it’s being used on the road.

This is also known as gross vehicle weight (GVW) or permissible maximum weight.

Plating Certificate

The vehicle weight and axle limits will be listed in the owner’s manual and normally shown on a plate or sticker fitted to the vehicle.

This may also show a gross train weight (GTW), also sometimes called gross combination weight (GCW). Which is the total weight of the tractor unit plus trailer and load.

The total weight transmitted to the road by all the wheels on one axle.

The weight of a vehicle and its load.

The weight of a vehicle, a trailer and its load.

Either the design weight limit given on a manufacturer’s plate or the legal weight limit given on the department’s plate.

A trailer pulled by a rigid vehicle.

Vehicles are limited to a maximum of 6 axles, and limited to an overall maximum weight of 44 tonnes

• *If the driving axle, if it is not a steering axle, has twin tyres and road friendly suspension, or each driving axle is fitted with twin tyres and the maximum weight for each axle does not exceed 8.55 tonnes
• **Distance between the rear axle of the motor vehicle and the front axle of the trailer is not less than 3 metres
• ***If the vehicle is being used for combined transport
• Note A: 5 axles or more artic and the 5 axles or more drawbar could alternatively have a 3 axle motor vehicle and a 2 axle trailer
• Note B: Conditions:
  - each vehicle must have at least 3 axles.
  - drive axle has twin tyre and road friendly suspension and maximum of 10.5 tonnes, or each driving axle is fitted with twin tyres and has a maximum of 8.5 tonnes
  - trailer has road friendly suspension
• Note C: Conditions for operation on 5 axles:
  - must have 3 axles on tractor unit
  - single container 40ft in length conforming to standards laid down by the International Standards Organisation being carried only
  - vehicle being used for international journey
• Note D: Powered by a low pollution engine

An ‘abnormal load’ is a vehicle that has any of the following:

• A weight of more than 44,000 kilograms
• An axle load of more than 10,000 kilograms for a single non-driving axle and 11,500 kilograms for a single driving axle
• A width of more than 2.9 metres
• A rigid length of more than 18.65 metres

Projection Markers

A load that projects more than 2 metres to the front or rear of the vehicle must be fitted with an end marker.

Back Title

Side markers must be displayed if your load is over 2.9 metres (9 feet 5 inches) wideor if the front or rear projection exceeds 3 metres.

If you’re responsible for transporting an abnormal load, you need to follow regulations for notifying the authorities.

Depending on the load you’re moving and your route, you may need to give advance warning to the police, highway authorities and bridge and structure owners such as Network Rail

Vehicles carrying loads between 4.3 metres (14 feet 1 inch) and 5 metres (16 feet 6 inches) wide are subject to lower speed limits. The limit depends on the type of road.

Special Types General Orders or STGOs are a set of regulations that allow unusual vehicles to be driven on UK highways. An STGO will indicate which category a vehicle is licenced to operate within

Examples of vehicles likely to be used under an STGO are:

• Abnormal Indivisible Loads (AILs) which cannot be divided in to two or more loads to be transported by road
• Mobile cranes specially built or adapted for lifting operations
• Engineering machinery that are moveable and comprise of a motor vehicle or trailer specially built for engineering operations
• Road recovery vehicles which are specifically build for recovering broken down vehicles.

There are three weight categories of STGOs:

Category 1 – max gross vehicle weight N/A and max category gross weight 50,000kg

Category 2 – D x 7,500kg and max category gross weight 80,000kg

Category 3 – D x 12,500kg and max category gross weight 150,000kg

(where D = the distance in metres between the foremost and rearmost axles of the vehicle carrying the load; or, in the case of articulated vehicles the kingpin and the rearmost axle on the semi-trailer; or, in the case of any other description of combination, the foremost axle and the rearmost axle of the group comprising of all the vehicles in the combination that are carrying a load).

In order for a vehicle to be classed as STGO Cat 1 it must not exceed 46,000kg with a minimum of 5 axles, and 50,000kg with a minimum of 6 axles. In this category the AW regulations minimum weights apply to axle and the vehicle gross weights. All STGO Cat 1 vehicles must display a “STGO Cat 1” plate to the front of the towing vehicle.

Before an STGO Cat 1 vehicle is to be used on the highways a minimum 2 days’ notice must be issued to highways and bridge authorities about the weight. The police may need to be informed of the vehicles’ dimensions.

The speed restrictions enforced for STGO Cat 1 vehicles are maximum 60mph on motorway, maximum 50mph on dual carriageways and a maximum of 40mph on all other roads.

An STGO Category 2 vehicle must not exceed 80,000kg. There are a number of other conditions that apply to the category. Category 2 vehicles must have a minimum of 6 axles, with the combined axle weight not exceeding 12,500kg.

In addition, a vehicle in this category must display the “STGO Cat 2” plate to the front of the towing vehicle. Where an STGO Cat 2 vehicle is to be used, there must be 2 working days’ notice to all relevant highway and bridge authorities. It may also be necessary to inform the police of the dimensions of the vehicle/s.

STGO Cat 2 vehicles are subject to specific speed restrictions. The speed limit on a motorway is 40mph, on a dual carriageway it is 35mph and just 30mph on other roads.

The STGO Cat 2 plate displayed on the vehicle must show the maximum weight recommended by the vehicle manufacturer when travelling at certain speeds. This plate must be marked “Special Types Use” and should show the weights for gross, train and axle weights.

STGO Category 3 vehicles can not exceed 150,000kg. They must have a minimum of 6 axles and have a maximum axle weight of 16,500kg.

It is essential that these vehicles display an STGO Cat 3 plate at the front of the drawing vehicle.

Due to the exceptional size and weight of these Cat 3 vehicles, operators must give at least 5 working days’ notice to highways and bridge authorities and as with Cat 1 and Cat 2 vehicles the dimensions may need to be given to the police.

As you would expect, the speed limits imposed on Cat 3 vehicles are even more restrictive. Motorway speed is limited to 40mph, dual carriageway speed is limited to 35mph and a maximum speed limit of 30mph is enforceable on other roads.

STGO Category 2 and STGO Category 3 vehicles must also be fitted with a plate that shows the maximum weight recommended by the vehicle manufacturer when travelling at certain maximum speeds. This plate must be marked “Special Types Use” and should show the weights for gross and train.

Telephone lines

You should tell telephone companies about your intended route when planning the movement of loads over 5.25 metres (17 feet 6 inches) high.

You should notify them in plenty of time before making the journey.

Electrical cables

Electrical cables spanning public roads should be no less than 5 metres (16 feet 6 inches) unless signage says otherwise

The headroom under bridges in the UK is at least 5 metres (16 feet 6 inches) unless marked otherwise. However, this might refer only to the highest point of an arch.

Bridges less than this will display a sign indicating the height of the bridge.

If your vehicle hits a bridge, you must report the incident to the police. If a railway bridge is involved, you must also report it to the railway authority quoting the bridge identification number which will be displayed on a sign under or near the bridge

If your vehicle is too long to fit into a passing place, you may need to wait opposite one.

This will allow a following or approaching driver to pass. When you use this type of road, you need to plan and look well ahead to avoid meeting another road user at an inappropriate place.

If your lorry is over 17 metres (55 feet) long and you wish to cross a level crossing, you must stop before the crossing and telephone the signal operator.

Diminishing loads

Drivers should be wary about axle overloads when removing large portions of the load from either the front or the vehicle's rear. The remaining load may need re-distribution to avoid the axles becoming overloaded.

1. Question 1 of 71. Question

   Sally has been asked to calculate the payload for an unladen vehicle.

   The unladen weight of any vehicle is the weight of the vehicle when it

   • Is not carrying any crew, goods, fuel or other items.
   • Is not carrying any passengers, goods or other items but includes a full tank of fuel
   • Is carrying passengers, goods or other items and includes a full tank of fuel
   • Is carrying crew, goods, fuel or other items.
   Correct
   Incorrect

2. Question 2 of 72. Question

   The Kerbside weight is slightly different to the unladen weight and includes

   • A tank of fuel
   • The weight of the crew
   • Additional items such a a hiab forklift
   • The weight of the goods being carried
   Correct
   Incorrect

3. Question 3 of 73. Question

   Sally needs to work know the maximum authorised mass (MAM) of the vehicle

   This includes

   • The weight of a vehicle or trailer including the maximum load that can be carried safely when it’s being used on the road.
   • The weight of a vehicle or trailer including the maximum load that can be carried safely when it’s being used on the road excluding the weight of the crew
   • The weight of a vehicle or trailer including the maximum load that can be carried safely when it’s being used on the road excluding the weight of additional items
   • The weight of a vehicle or trailer including the maximum load that can be carried safely when it’s being used on the road excluding the weight of the fuel
   Correct
   Incorrect

4. Question 4 of 74. Question

   An STGO category 1 vehicle must have a gross vehicle weight of no more than

   • 50,000 kg
   • 80,000kg
   • 44,000kg
   • 40,000kg
   Correct
   Incorrect

5. Question 5 of 75. Question

   Unless signage indicates otherwise, electrical cables spanning public roads should be no less than

   • 16 ft
   • 16 ft 6 inches
   • 15ft
   • 15 ft 8 inches
   Correct
   Incorrect

6. Question 6 of 76. Question

   You must stop before a level crossing and telephone the signal operator if your vehicle is longer than

   • 55 feet
   • 47 feet
   • 62 feet
   • 86 feet
   Correct
   Incorrect

7. Question 7 of 77. Question

   The maximum GVW of a 3 axle artic vehicle is

   • 26 tonnes
   • 30 tonnes
   • 32 tonnes
   • 40 tonnes
   Correct
   Incorrect