Looking after a car in hot weather

Sunlight across the side window of a car

Heat works on coolant, tires and batteries in ways that are easy to miss. What to check when the temperature climbs.

Hot weather is quieter on a car than winter, but it is not gentler. Engines run hotter, tires heat up on sun-baked roads and batteries, oddly, can be worn down more by heat than by cold. A few checks at the start of summer go a long way.

Coolant and the temperature gauge

With the engine cold, check that the coolant sits between its marks. On the road, glance at the temperature gauge now and then. If it climbs higher than usual, turning off the air conditioning and turning the heater up can take some load off; pull over safely if it keeps rising.

Never open a hot coolant or radiator cap. Wait until the engine has cooled completely.

Tires on hot roads

Pressure rises as tires warm up, so check it in the cool of the morning, not after a drive. Underinflated tires flex more and build up more heat, which is one more reason to keep them at the figure on the door sticker.

People and pets

The inside of a parked car heats up fast, even with the windows open a crack. Never leave a child or an animal in a parked car, and take a look in the back seat before you lock up. Carry extra water on long drives.

  • Coolant checked with the engine cold
  • Tire pressure checked in the morning
  • Water in the car for everyone on board
  • A look in the back seat before locking
A drilled brake disc and caliper behind a removed wheelBrakesThe suspension and wheel of a car seen from underneathSteering and suspension

This article is general information, not advice about your own car. Follow your owner’s manual and ask a qualified technician about anything you are unsure of.

Related guides:BrakesSteering and suspension

// Road notes

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