Traffic signsSouth Africa

An introduction to the traffic rules and road signs of South Africa. Learn about driving, road safety and much more in our illustrated book, with answers to frequently asked questions.

For informational purposes only. Always follow official regulations. Some content and images were created with AI assistance.


126. Hands-free

Hands-free refers to using a telephone or communication system without holding the device in the hand. Hands-free operation can use the vehicle's built-in system, a headset, earphones, voice control or a phone secured in an appropriate holder.

Hands-free operation reduces the need to physically handle a device, but a conversation or interaction can still distract the driver. Drivers should therefore minimise device use and keep their attention on the road.

Hands-free
View from a vehicle travelling on the A42 motorway towards Bourg. (France)
Wikimedia.org • Benoît Prieur • CC0

127. Smartphone

A smartphone is a mobile electronic device that combines telephone, messaging, internet, navigation, camera and application functions. When used in traffic, a smartphone can provide useful functions such as navigation or hands-free communication but can also create significant visual, manual and mental distraction.

Drivers should avoid handling or looking at a smartphone while driving. Where its use is permitted, the device should be positioned and operated in accordance with local traffic rules and without interfering with safe control of the vehicle.

Smartphone
Smartphone displaying a mobile foreign-exchange trading application.
Wikimedia.org • D'Vaughn Bell • CC BY-SA

128. GPS

GPS (Global Positioning System) is a satellite-based positioning and navigation system that allows a compatible device to determine its location. In vehicles, GPS navigation can combine positioning information with digital maps to calculate routes and provide visual or spoken directions.

Drivers should preferably set their destination before starting the journey and avoid unnecessary interaction with the navigation system while driving. GPS directions are advisory and should never be followed when they conflict with traffic signs, road rules or actual road conditions.

GPS
A GPS helping a driver navigate the roads.
Wikimedia.org • ines s. • CC BY
What does GPS do in a vehicle?

A GPS receiver helps determine the vehicle’s position from satellite signals. Navigation software combines that position with digital maps to calculate routes and give directions. GPS positioning and the map or routing information are separate parts of the system.

🔗 gps.gov • US GPS programme, receiver positioning

🔗 ford.com • Ford, automotive terminology glossary

Should you program a GPS while driving?

It is safer to enter the destination and adjust the route before starting the journey. If significant changes are needed, stop in a safe and permitted place rather than becoming distracted while driving.

🔗 gov.uk • Great Britain Highway Code, Rule 97, journey preparation and controls; national guidance example

🔗 gov.uk • Great Britain Highway Code, Rules 144–150, distraction and aggressive behaviour; national guidance example

🔗 gov.uk • Great Britain Highway Code, Rules 159–169, observation; national guidance example

🔗 wetten.overheid.nl • Vienna Convention on Road Traffic, Articles 7–8 and 13; international framework subject to national law

129. Brake

A brake is a vehicle system used to reduce speed, bring the vehicle to a stop or keep it stationary. Most road vehicles use friction brakes at the wheels, while electric and hybrid vehicles may also use regenerative braking to recover energy while slowing down.

The braking system must remain in good working condition. Worn brake components, overheating, mechanical faults or reduced tyre grip can increase braking distance and reduce the driver's ability to control the vehicle safely.

Brake

130. Handbrake

A handbrake, commonly called the parking brake, is a braking system used to keep a stationary vehicle from moving after it has been parked. Traditional systems use a hand-operated lever, while modern vehicles may use a foot-operated or electronic parking brake.

The parking brake should be applied securely whenever the vehicle is parked, particularly on a slope. It operates separately from the normal service brake so that the vehicle can remain stationary even when the driver is absent.

A manual handbrake of a Porsche 911.
Wikimedia.org • CC BY-SA

131. Brake fluid

Brake fluid is a hydraulic fluid used in many vehicle braking systems to transmit force from the brake pedal through the hydraulic system to the brakes at the wheels. It must withstand high temperatures and maintain suitable hydraulic properties for reliable braking.

The brake-fluid level and condition should be checked according to the vehicle manufacturer's instructions. Only the specified type of brake fluid should be used, because incompatible or contaminated fluid can impair braking-system performance.

Brake fluid
The brake fluid reservoir in a Škoda Fabia.
Wikimedia.org • Frettie • CC BY

132. Tyres

Tyres are the rubber components fitted around a vehicle's wheels that provide contact with the road. They transmit braking, acceleration and steering forces and play an important role in vehicle stability and road holding.

Tyres should have sufficient tread depth, correct pressure and no serious damage or excessive wear. Drivers should use tyres that are suitable for the vehicle and regularly check their condition, particularly before long journeys or driving in difficult weather.

Tyres
Close-up of tyre tread.
Wikimedia.org • Ambiguous • CC BY
Why are tyres important for road safety?

Tyres are the vehicle's contact with the road and transmit the forces required for steering, acceleration and braking. Their condition and available grip therefore directly affect vehicle control.

🔗 michelin.co.uk • Michelin, tyre sidewall markings and sizing

🔗 michelin.co.uk • Michelin, winter tyres, conditions and markings

🔗 gov.uk • Great Britain Highway Code, Annex 6, tyres and pressures; national guidance example

🔗 gov.uk • Great Britain Highway Code, Rules 228–231, snow and ice; national guidance example

🔗 cdn.group.renault.com • Dacia Sandero, Stepway and Jogger owner’s manual, pages 4.12–4.13 and 5.2–5.16, tyres, spare wheel and pressure; model-specific example

🔗 hseni.gov.uk • Health and Safety Executive Northern Ireland, supporting vehicles safely during repair

Should tyres on the same axle match?

Requirements vary between countries, but tyres fitted to the same axle should be compatible in dimensions, construction and performance. National rules may impose specific matching requirements.

🔗 michelin.co.uk • Michelin, tyre sidewall markings and sizing

🔗 michelin.co.uk • Michelin, winter tyres, conditions and markings

🔗 gov.uk • Great Britain Highway Code, Annex 6, tyres and pressures; national guidance example

🔗 gov.uk • Great Britain Highway Code, Rules 228–231, snow and ice; national guidance example

🔗 cdn.group.renault.com • Dacia Sandero, Stepway and Jogger owner’s manual, pages 4.12–4.13 and 5.2–5.16, tyres, spare wheel and pressure; model-specific example

🔗 hseni.gov.uk • Health and Safety Executive Northern Ireland, supporting vehicles safely during repair

133. Tyre code

A tyre code is the series of letters and numbers marked on a tyre's sidewall that identifies important characteristics such as tyre width, aspect ratio, construction, wheel diameter, load capacity and speed rating. A typical example is 205/55 R16 91V.

Drivers should use tyres whose specifications are suitable for the vehicle. The required tyre sizes and ratings can normally be found in the vehicle handbook, certificate of conformity or other manufacturer information.

Tyre code
Diagram explaining the markings in a tyre code.
Wikimedia.org • F l a n k e r • CC BY
What does a tyre code such as 205/55 R16 mean?

205 indicates the nominal tyre width in millimetres, 55 is the aspect ratio between sidewall height and tyre width, R indicates radial construction and 16 indicates the diameter of the wheel rim in inches.

🔗 michelin.co.uk • Michelin, tyre sidewall markings and sizing

🔗 michelin.co.uk • Michelin, winter tyres, conditions and markings

🔗 gov.uk • Great Britain Highway Code, Annex 6, tyres and pressures; national guidance example

🔗 gov.uk • Great Britain Highway Code, Rules 228–231, snow and ice; national guidance example

🔗 cdn.group.renault.com • Dacia Sandero, Stepway and Jogger owner’s manual, pages 4.12–4.13 and 5.2–5.16, tyres, spare wheel and pressure; model-specific example

🔗 hseni.gov.uk • Health and Safety Executive Northern Ireland, supporting vehicles safely during repair

What other markings can appear on a tyre?

Tyres can carry additional markings indicating approval, manufacturer information, production date, suitability for winter conditions, reinforced construction or other technical characteristics. The exact markings depend on the tyre type and applicable standards.

🔗 michelin.co.uk • Michelin, tyre sidewall markings and sizing

🔗 michelin.co.uk • Michelin, winter tyres, conditions and markings

🔗 gov.uk • Great Britain Highway Code, Annex 6, tyres and pressures; national guidance example

🔗 gov.uk • Great Britain Highway Code, Rules 228–231, snow and ice; national guidance example

🔗 cdn.group.renault.com • Dacia Sandero, Stepway and Jogger owner’s manual, pages 4.12–4.13 and 5.2–5.16, tyres, spare wheel and pressure; model-specific example

🔗 hseni.gov.uk • Health and Safety Executive Northern Ireland, supporting vehicles safely during repair

134. Winter tyres

Winter tyres are tyres designed to provide improved traction and braking performance in cold weather, snow and other winter conditions. Their tread pattern and rubber compound are designed to remain effective at lower temperatures and provide better grip than ordinary summer tyres in appropriate winter conditions.

Winter tyres can be identified by markings on the sidewall. The 3PMSF symbol, showing a snowflake inside a three-peaked mountain, indicates that the tyre has met specified performance requirements for severe snow conditions.

Winter tyres
Winter tyre displaying mountain-and-snowflake symbol.
Wikimedia.org • A7N8X • CC BY-SA

135. Tyre pressure

Tyre pressure is the amount of air pressure inside a vehicle's tyre. Correct tyre pressure helps the tyre maintain its intended shape and contact with the road and is important for handling, braking, tyre wear and fuel consumption.

Tyre pressure should be checked regularly and adjusted to the pressure specified by the vehicle manufacturer. The recommended pressure can vary according to the vehicle, tyre size and load, and the front and rear tyres may require different pressures.

Checking tyre pressure with a pressure gauge.
Wikimedia.org • JEG14 • CC0
Why is correct tyre pressure important?

Correct tyre pressure helps provide predictable handling, braking and tyre wear. Incorrect pressure can reduce performance, increase tyre wear and increase fuel consumption.

🔗 michelin.co.uk • Michelin, tyre sidewall markings and sizing

🔗 michelin.co.uk • Michelin, winter tyres, conditions and markings

🔗 gov.uk • Great Britain Highway Code, Annex 6, tyres and pressures; national guidance example

🔗 gov.uk • Great Britain Highway Code, Rules 228–231, snow and ice; national guidance example

🔗 cdn.group.renault.com • Dacia Sandero, Stepway and Jogger owner’s manual, pages 4.12–4.13 and 5.2–5.16, tyres, spare wheel and pressure; model-specific example

🔗 hseni.gov.uk • Health and Safety Executive Northern Ireland, supporting vehicles safely during repair

Should tyre pressure be checked regularly?

Yes. Tyres gradually lose air over time, so their pressure should be checked regularly and before demanding or long journeys. The pressure should be adjusted to the manufacturer's recommended value.

🔗 michelin.co.uk • Michelin, tyre sidewall markings and sizing

🔗 michelin.co.uk • Michelin, winter tyres, conditions and markings

🔗 gov.uk • Great Britain Highway Code, Annex 6, tyres and pressures; national guidance example

🔗 gov.uk • Great Britain Highway Code, Rules 228–231, snow and ice; national guidance example

🔗 cdn.group.renault.com • Dacia Sandero, Stepway and Jogger owner’s manual, pages 4.12–4.13 and 5.2–5.16, tyres, spare wheel and pressure; model-specific example

🔗 hseni.gov.uk • Health and Safety Executive Northern Ireland, supporting vehicles safely during repair

136. Snow chains

Snow chains are traction devices fitted around vehicle tyres to improve grip on roads covered with snow or ice. They are especially useful on steep or mountainous roads where ordinary tyres may not provide sufficient traction.

Snow chains should be fitted according to the vehicle and chain manufacturer's instructions, normally on the driven wheels. They should be removed when they are no longer needed because driving with chains on clear roads can damage the tyres, chains and road surface.

Snow chains
Snow chain fitted to a Honda vehicle.
Wikimedia.org • Domitori • CC BY-SA

137. Bicycle tyre

A bicycle tyre is the rubber tyre fitted around a bicycle wheel and provides contact between the bicycle and the road or other riding surface. Its tread, pressure, width and construction affect grip, rolling resistance, comfort and handling.

Bicycle tyres should be properly inflated and regularly checked for wear, cuts, cracks, embedded objects or other damage. The appropriate tyre type and pressure depend on the bicycle, rider, load and riding conditions.

Bicycle tyre
Why are bicycle tyres important for safety?

Bicycle tyres provide the grip needed for steering and braking and help absorb irregularities in the road surface. Worn, damaged or incorrectly inflated tyres can reduce control and increase the risk of a puncture or loss of grip.

🔗 michelin.co.uk • Michelin, choosing bicycle tyres, road/off-road tread and intended use

Do all bicycles use the same type of tyre?

No. Choose tyres suited to the bicycle and riding conditions. Road and off-road tyres make different compromises between rolling resistance, grip and puncture protection; mountain-bike tyres typically have more pronounced tread for rough or muddy ground.

🔗 michelin.co.uk • Michelin, choosing bicycle tyres, road/off-road tread and intended use

138. Continuous track

Continuous track is a vehicle propulsion system in which a continuous belt or chain runs around a series of wheels or rollers instead of the vehicle travelling on conventional road wheels. It is commonly used on construction machinery, agricultural vehicles, military vehicles and other machines that need good traction on soft or uneven ground.

Continuous tracks spread the vehicle's weight over a relatively large contact area, which can improve traction and reduce ground pressure. Tracks may be made from metal, rubber or a combination of materials, and their suitability for use on public roads depends on the vehicle and applicable regulations.

Continuous track
Large tracked construction crane. (Auckland, New Zealand)
Wikimedia.org • Ingolfson • CC0
Can tracked vehicles travel on normal roads?

Some can, subject to the local vehicle and road-use requirements. For example, British rules allow qualifying tracked agricultural vehicles on roads only with rubber or other composite tracks that do not damage the surface. Registration, driver entitlement and other vehicle restrictions must also be checked.

🔗 legislation.gov.uk • UK legislation, special-type vehicles and rubber tracks

🔗 gov.uk • DfT, tractors and tracked vehicles on public roads

139. Gross Vehicle Weight

Gross Vehicle Weight (GVW) is the actual total weight of a vehicle at a particular moment, including the vehicle itself, driver, passengers, fuel, luggage and other cargo. It changes as people or goods are added or removed.

GVW should not be confused with Gross Vehicle Weight Rating (GVWR) or Maximum Authorised Mass (MAM), which is the maximum permitted total weight specified for the vehicle. The actual gross vehicle weight must not exceed that permitted maximum.

What does Gross Vehicle Weight include?

The actual laden mass includes the vehicle, occupants, fuel, luggage, cargo and equipment being carried. Be careful with the term Gross Vehicle Weight: some authorities, including British guidance, use GVW for a maximum authorised weight rather than the actual mass at that moment. Check the definition on the document.

🔗 ecfr.gov • US 49 CFR 571.3, GVWR/GCWR manufacturer definitions; US example

🔗 gov.uk • GOV.UK, vehicle weights explained, MAM/GVW and down-plating; British example

🔗 cdn.group.renault.com • Dacia Sandero, Stepway and Jogger owner’s manual, pages 3.48–3.60 and 6.6–6.8, loading, roof bars and maximum masses; model-specific example

🔗 wetten.overheid.nl • Vienna Convention on Road Traffic, Article 30, load securing and projection; international framework subject to national law

Why is Gross Vehicle Weight important?

Actual loaded mass and the permitted ratings both matter. Stay within applicable total, axle, tyre and combination limits, and secure and distribute the load correctly. Do not assume that a figure labelled GVW always means the vehicle’s current measured mass.

🔗 ecfr.gov • US 49 CFR 571.3, GVWR/GCWR manufacturer definitions; US example

🔗 gov.uk • GOV.UK, vehicle weights explained, MAM/GVW and down-plating; British example

🔗 cdn.group.renault.com • Dacia Sandero, Stepway and Jogger owner’s manual, pages 3.48–3.60 and 6.6–6.8, loading, roof bars and maximum masses; model-specific example

🔗 wetten.overheid.nl • Vienna Convention on Road Traffic, Article 30, load securing and projection; international framework subject to national law

140. Gross Vehicle Weight Rating

Gross Vehicle Weight Rating (GVWR) is the maximum total weight at which a vehicle is designed or approved to operate when fully loaded. It includes the vehicle itself together with the driver, passengers, fuel, luggage, cargo and other equipment carried by the vehicle.

GVWR is a fixed maximum value and should not be confused with Gross Vehicle Weight (GVW), which is the vehicle's actual weight at a particular moment. The actual loaded weight of the vehicle must not exceed its permitted maximum.

What does GVWR include?

GVWR is the loaded-weight rating specified by the manufacturer for a single vehicle. It covers the vehicle and everything carried, including occupants, fuel and cargo. The legal mass allowed on a particular journey may also be limited by registration, axle, road or other rules.

🔗 ecfr.gov • US 49 CFR 571.3, GVWR/GCWR manufacturer definitions; US example

🔗 gov.uk • GOV.UK, vehicle weights explained, MAM/GVW and down-plating; British example

🔗 cdn.group.renault.com • Dacia Sandero, Stepway and Jogger owner’s manual, pages 3.48–3.60 and 6.6–6.8, loading, roof bars and maximum masses; model-specific example

🔗 wetten.overheid.nl • Vienna Convention on Road Traffic, Article 30, load securing and projection; international framework subject to national law

Why is GVWR important?

GVWR helps identify the manufacturer’s loading limit and can be relevant to vehicle and licensing classifications. Check every applicable limit: a lower plated, axle, tyre or road limit may also apply. Staying below one total rating does not excuse an overloaded axle or an insecure load.

🔗 ecfr.gov • US 49 CFR 571.3, GVWR/GCWR manufacturer definitions; US example

🔗 gov.uk • GOV.UK, vehicle weights explained, MAM/GVW and down-plating; British example

🔗 cdn.group.renault.com • Dacia Sandero, Stepway and Jogger owner’s manual, pages 3.48–3.60 and 6.6–6.8, loading, roof bars and maximum masses; model-specific example

🔗 wetten.overheid.nl • Vienna Convention on Road Traffic, Article 30, load securing and projection; international framework subject to national law

141. Cargo

Cargo is the goods, materials, equipment or other items carried by a vehicle or trailer. Cargo can range from personal luggage and bicycles to commercial goods, machinery or bulk materials.

Cargo must be positioned and secured so that it cannot shift, fall from the vehicle, interfere with the driver's visibility or affect vehicle stability. The total load must also remain within the vehicle's permitted weight and axle-load limits.

142. Car body

A car body, also called bodywork, is the outer structure of a car that surrounds the passenger and luggage compartments and gives the vehicle its shape. It includes components such as the roof, doors, bonnet, boot lid, wings, body panels and, on many modern cars, load-bearing structural sections.

The car body helps protect occupants and supports components such as doors, windows, lights and bumpers. Damage, corrosion or poorly repaired structural sections can reduce the vehicle's safety and should be repaired correctly.

Car body

143. Trunk

A trunk, also called a boot or luggage compartment, is the enclosed storage area of a car used for carrying luggage, tools, shopping and other cargo. It is usually located at the rear of the vehicle, although some vehicles have a front storage compartment.

Items carried in the trunk should be positioned securely so that they cannot shift dangerously during braking, acceleration or cornering. Heavy objects should be placed carefully and the vehicle's permitted load and axle limits must not be exceeded.

Trunk
Luggage compartment of a Car2Go Smart car. (Seattle, Washington, United States)
Wikimedia.org • Atomic Taco • CC BY-SA

144. Roof rack

A roof rack is a load-carrying system attached to the roof of a vehicle. It can be used to transport items such as luggage, bicycles, skis, surfboards or a roof box when they cannot conveniently be carried inside the vehicle.

A roof rack and its cargo must be securely attached and must remain within the vehicle manufacturer's permitted roof-load limit. Roof-mounted loads raise the vehicle's centre of gravity and can affect handling, stability, fuel consumption and overall vehicle height.

Mercedes-Benz E-Class estate fitted with a roof box.
Wikimedia.org • Matti Blume • CC BY-SA

145. Windscreen

A windscreen, also called a windshield, is the transparent front window of a vehicle through which the driver views the road ahead. It also helps protect occupants from wind, rain, debris and other external elements.

The windscreen must provide the driver with a clear and sufficiently undistorted view. Cracks, chips, dirt, stickers or other objects can reduce visibility, particularly when they are located within the area swept by the windscreen wipers.

Large windscreen on a Scania truck.
Wikimedia.org • Vcx • CC BY-SA

146. Emergency hammer

An emergency hammer is a safety tool designed to break certain vehicle windows when normal doors or exits cannot be used during an emergency. It is commonly found in buses, coaches and other passenger vehicles near windows designated as emergency exits.

An emergency hammer should only be used when evacuation through the normal exits is impossible or unsafe. The tool must remain accessible and, where provided for an emergency window, should be used according to the instructions displayed in the vehicle.

Emergency hammer
An emergency hammer in a train.
Wikimedia.org • Santeri Viinamäki • CC BY-SA
What is an emergency hammer used for?

An emergency hammer is used to break a suitable vehicle window so occupants can escape when normal doors or emergency exits cannot be opened.

🔗 wegcode.be • Belgium, Technical Requirements Decree of 15 March 1968, bus emergency-window equipment and glazing provisions; national example

Can an emergency hammer break every vehicle window?

No. Vehicle windows can use different types of glazing, and not every window is designed to be broken as an emergency exit. Occupants should use designated emergency windows and follow the instructions provided in the vehicle.

🔗 wegcode.be • Belgium, Technical Requirements Decree of 15 March 1968, bus emergency-window equipment and glazing provisions; national example

147. Car battery

A car battery is an electrical energy-storage device that supplies power to a vehicle's electrical system. In conventional petrol and diesel cars, the 12-volt starter battery provides the high current needed to start the engine and supplies electrical equipment when the engine or charging system is not providing enough power.

Car batteries gradually lose charge and capacity with age and use. A weak battery can cause slow or unsuccessful starting, electrical problems or warning messages, and the replacement battery should have specifications suitable for the vehicle.

Car battery of a Volkswagen Golf.
Wikimedia.org • Filipograf • CC BY-SA
What does a car battery do?

A low-voltage vehicle battery powers electrical equipment and control systems. In many combustion-engine vehicles it also supplies the starter motor. In an electric-drive vehicle, the auxiliary battery has a different role from the high-voltage traction battery that supplies propulsion energy.

🔗 afdc.energy.gov • US Department of Energy AFDC, auxiliary versus traction battery

🔗 varta-automotive.com • VARTA, replacing AGM/EFB start-stop batteries

🔗 cdn.group.renault.com • Dacia Sandero, Stepway and Jogger owner’s manual, page 4.14, battery replacement precautions; model-specific example

Can any replacement battery be fitted to a car?

No. The battery must have specifications and technology suitable for the vehicle. Cars equipped with start-stop systems, for example, may require AGM or EFB battery technology designed for repeated starting and charging cycles.

🔗 afdc.energy.gov • US Department of Energy AFDC, auxiliary versus traction battery

🔗 varta-automotive.com • VARTA, replacing AGM/EFB start-stop batteries

🔗 cdn.group.renault.com • Dacia Sandero, Stepway and Jogger owner’s manual, page 4.14, battery replacement precautions; model-specific example

148. Traction battery

A traction battery is a rechargeable battery that stores electrical energy used to propel an electric or hybrid vehicle. It supplies power to one or more electric traction motors and is normally much larger and more powerful than the vehicle's conventional 12-volt starter battery.

Traction-battery capacity is commonly expressed in kilowatt-hours (kWh) and strongly influences an electric vehicle's driving range. Its performance and usable capacity can gradually decrease with age, charging cycles, temperature and use.

Traction battery
Lithium-ion traction batteries of a SOR EBN 11 electric city bus at IAA 2014. (Hanover, Germany)
Wikimedia.org • Spielvogel • CC0
What does a traction battery do?

A traction battery stores electrical energy and supplies it to the electric motor or motors that propel the vehicle. In hybrid vehicles it works together with another power source, while in battery-electric vehicles it provides the main source of propulsion energy.

🔗 afdc.energy.gov • US Department of Energy AFDC, all-electric vehicle components

🔗 afdc.energy.gov • US Department of Energy AFDC, fuel-cell electric vehicle components

🔗 afdc.energy.gov • US Department of Energy AFDC, hybrid-electric vehicle components

🔗 nist.gov • US NIST, energy units including kilowatt-hour

What does traction-battery capacity mean?

Battery capacity indicates how much electrical energy the battery can store and is commonly expressed in kilowatt-hours (kWh). A larger usable capacity generally allows more electrical energy to be available for driving.

🔗 afdc.energy.gov • US Department of Energy AFDC, all-electric vehicle components

🔗 afdc.energy.gov • US Department of Energy AFDC, fuel-cell electric vehicle components

🔗 afdc.energy.gov • US Department of Energy AFDC, hybrid-electric vehicle components

🔗 nist.gov • US NIST, energy units including kilowatt-hour

149. Suspension

Suspension is the system that connects a vehicle's wheels and axles to its body or chassis. It includes components such as springs, shock absorbers, control arms, joints and links that allow the wheels to move while helping keep the vehicle stable and comfortable.

The suspension helps maintain tyre contact with the road, absorbs bumps and contributes to steering, braking and vehicle stability. Worn or damaged suspension components can reduce handling and increase uneven tyre wear.

Suspension
Front swing-arm suspension of a Vespa PX scooter.
Wikimedia.org • Khaosaming • CC BY-SA
What does a vehicle suspension system do?

The suspension supports the vehicle, allows the wheels to move over uneven surfaces and helps keep the tyres in contact with the road while controlling body movement.

🔗 monroe.com • Monroe, shocks, struts and spring-support/damping functions

🔗 gov.uk • Great Britain Highway Code, Annex 6, suspension and maintenance; national guidance example

What are signs of worn suspension?

Possible signs include excessive bouncing, unusual noises, poor stability, uneven tyre wear, excessive body movement in bends or a vehicle that sits unevenly. These symptoms should be inspected because they can also have other causes.

🔗 monroe.com • Monroe, shocks, struts and spring-support/damping functions

🔗 gov.uk • Great Britain Highway Code, Annex 6, suspension and maintenance; national guidance example

150. Shock absorber

A shock absorber is a suspension component that controls the movement of a vehicle's springs and wheels. It reduces excessive bouncing after bumps and helps keep the tyres in consistent contact with the road.

Worn or damaged shock absorbers can reduce vehicle stability, increase body movement and negatively affect steering and braking behaviour. They should be inspected if the vehicle bounces excessively, handles poorly or shows signs of fluid leakage.

Shock absorber
Miniature oil-filled shock-absorber components for scale-model cars.
Wikimedia.org • Avsar Aras • CC BY-SA
What does a shock absorber do?

A shock absorber controls suspension movement by damping the repeated movement of the springs. This helps stabilise the vehicle and maintain tyre contact with the road.

🔗 monroe.com • Monroe, shocks, struts and spring-support/damping functions

🔗 gov.uk • Great Britain Highway Code, Annex 6, suspension and maintenance; national guidance example

Are shock absorbers the same as springs?

No. Springs support the vehicle and allow the suspension to move over bumps, while shock absorbers control and damp that movement. The two components work together as part of the suspension system.

🔗 monroe.com • Monroe, shocks, struts and spring-support/damping functions

🔗 gov.uk • Great Britain Highway Code, Annex 6, suspension and maintenance; national guidance example