A guide to driving in hot weather

What does hot weather do to cars?

While we’re more likely to experience grey mornings and rainy afternoons, the UK is getting hotter. With this summer already seeing the highest temperatures on record, many of us have been experiencing driving in hot weather for the first time. We all know the precautions we should take when spending time out in the sunshine: applying factor 50 suncream, wearing sunglasses, and staying hydrated – but what about our cars?  

The heat can have several effects on our vehicles when driving in the summer.  

Read on for our top summer safe driving tips:  

9 summer driving tips  

Check your tyres  

Tyres are temperamental things. Not only do they wear down over time and can get punctures when running over rough ground, but they can also be affected by summer driving. Tyre rotation puts pressure on the rubber surface and heat can amplify this stress. Heat also makes the air inside the tyre expand and over-inflate, which can result in bubbling, punctures, and even potential blow-outs. It’s important to get into the habit of assessing the condition of your tyres regularly to ensure that they have good pressure and a thick tread before setting off.  

Protect your paintwork  

If you park your car on the road or in an open-air car park during the summer months, your paintwork could take a hit. An extended period time in direct sunlight can fade the car’s colour and even cause cracks in your bodywork. Not cleaned your car in a while? It could be even more at risk! Debris like leaves, twigs, or bird droppings can cause more damage when combined with sunshine. Try to find sheltered parking locations, especially during the day, and clean off any dirt or debris with cool, but not ice cold, water.  

Monitor battery life 

High temperatures can also affect your car battery. Batteries are made up of acid and water, and hot weather in the UK can cause the water to evaporate. This, in turn, makes the chemical operation of the battery work overtime and it can struggle to hold charge and produce enough power. Batteries are also put under more pressure thanks to air conditioning, fans, windows being opened and closed, and convertible roofs being rolled back. This can shorten the battery’s lifespan and cause your car to breakdown without warning.  

Service your air conditioning 

With the UK experiencing mild weather for most of the year, many of us don’t reach for our air conditioning until temperatures really start climbing. Ignoring your air-con for months on end and then suddenly using it for several days can cause problems. Try to remember your air conditioning all year round and book in with a garage to get it regularly serviced. If you do turn it on and notice a new or strange smell then that could mean your system is damaged; there might be a leak, low refrigerant level, or it could need a deep clean.  

Top up your coolant 

A hot summer day can affect all your car’s fluids so it’s important to keep an eye on their levels. Vehicles rely on their coolant system to keep the engine cool but, in the heat, this liquid moves around the engine at a higher temperature, which can cause some parts of the engine to overheat and fail. It’s more likely to happen when travelling at low speeds when there’s less air circulating through the fan at the front of the car so be especially careful if you tend to get stuck in a lot of stop/start traffic.  

Check your engine oil 

Your car uses its oil and coolant to keep its engine lubricated and chilled but, like coolant, your engine oil will also get warmer in the heat and can even thin slightly. Unfortunately, thinner oil circulating around the engine will mean that some parts won’t get the protection they need, increasing the amount of friction and making it more likely that the engine will be damaged.  

Drive carefully 

While you might be tempted to get to your destination as quickly as possible, driving erratically in the heat isn’t just dangerous, it can also cause unnecessary wear and tear. Coasting, braking harshly, and accelerating too quickly can all put pressure on an engine that’s already working hard. Road conditions can also be tough in hot weather as tarmac gets softer or slippery if it starts raining again after a long dry spell. Driving carefully, anticipating other drivers’ actions, and avoiding congested roads can all decrease your chances of breaking down in hot weather.  

Fill your tank  

Your fuel gauge can be misleading in hot weather. During the summer, your fuel levels can drop faster than usual so your normal estimations might not be right. To avoid being stranded on the side of the motorway with the sun beating down on you, err on the side of caution and don’t let your fuel levels get too low before filling up again.  

Keep your car well ventilated  

It’s not just advice; Rule 237 of the Highway Code says that you must keep your vehicle well ventilated to avoid drowsiness in hot weather. Get a good night’s sleep before any long drives, take plenty of breaks, and make sure that you have cold air flowing, whether it’s from an open window or your air conditioning so that you can keep your concentration sharp.  

Should you drive during a heatwave?  

As a driver in the summer, you might not have any choice but to get behind the wheel. With public transport affected by the extreme heat and essential workers and school children needing to travel, you can’t always choose to stay at home.  

Even so, hot temperatures can make cars vulnerable to overheating and dead batteries. In fact, a recent AXA report showed that cars are 50% more likely to overheat in warm weather and that’s the leading cause of breakdowns in the UK. If you can keep your car parked in a secure garage or shady spot and not venture out in the heat, that might be the best option for you and your vehicle.  

Summer Driving Advice: Drivers and Passengers  

For a driver or passenger, many of the same rules apply when travelling in a car as when walking in the summer sun.  

• Invest in a windscreen shield to help keep the sun out of your car when you have to park in the sun to keep the interior cooler. 
• Apply suncream to protect your skin. Sun rays can penetrate the windows of your car leaving you vulnerable to sunburn and sunstroke.  
• Wear sunglasses to protect your eyes and cut down on any glare caused by the sun reflecting on the windscreen. 
• Take hay fever medication if you’re affected by high pollen counts.  
• Stay hydrated and always carry a bottle of water. Make sure not to leave fizzy drinks in your car as these can overheat and explode.  

• Don’t leave any small children or pets in your car.  

How to pick the perfect summer driving songs 

Summer driving typically means long road trips, visits to the beach, and travelling with friends and family – all journeys that deserve a good soundtrack. To create a great summer playlist there are a few things to consider. It’s always a good idea to plan in advance so that you’re not trying to make changes as you drive, crowd source suggestions from your passengers, choose a theme, or try to match your music to your surroundings.  

Some of our favourite driving song choices include:  

• Born to Run – Bruce Springsteen 

• Sweet Home Alabama – Lynyrd Skynyrd 
• Fast Car – Tracy Chapman 
• Wake Me Up – Avicii 
• Summertime – DJ Jazzy Jeff  
• Summer of ‘69 - Bryan Adams  

• Don’t Stop Believin’ - Journey 
• California – Phantom Planet  
• Every Day is a Winding Road – Sheryl Crow