Summer Heat and Your Car: What to Check

Summer is tough on cars. High temperatures put extra stress on cooling systems, batteries, tires, and air conditioning, often all at once. A little checking before and during hot weather can help you avoid being stranded on the side of the road in the heat.

Cooling system

Your engine's cooling system works hardest in summer, especially in traffic or while towing.

Check these:

• Coolant level. Look at the overflow reservoir with the engine cold. Never open a hot radiator cap.
• Coolant condition. It should look clean, not rusty, oily, or sludgy.
• Hoses. Squeeze them when cool. They shouldn't be brittle, swollen, or soft.
• Radiator. Clear bugs, leaves, and debris from the front of the radiator and AC condenser.
• Cooling fans. With the AC on, the electric fan should run.

If the temperature gauge climbs, turn off the AC and turn the heater on full to pull heat away from the engine, then pull over safely and let it cool. See what cooling system coverage typically includes.

Battery

Many people think cold kills batteries, but heat does a lot of the damage. High temperatures speed up the chemical wear inside a battery, and the failure often shows up later when it's cold.

• Ask a shop or parts store to test your battery, which many do at no charge
• Look for corrosion on terminals and clean it if needed
• Make sure the battery is held down firmly
• If your battery is getting older, consider replacing it before it leaves you stuck

Air conditioning

AC problems tend to show up on the first truly hot day. Warning signs include:

• Air that's cool but not cold
• Cold air that turns warm after a while
• Clicking or grinding when the AC turns on
• Musty smells from the vents
• Water dripping inside the cabin instead of under the car

Low refrigerant usually means a leak somewhere. A compressor replacement can be expensive. Learn more about auto AC coverage.

Tires

Hot pavement and underinflation are a bad combination. A tire running low on air flexes more and builds more heat.

• Check pressures monthly, in the morning before driving
• Use the pressure on the door jamb sticker, not the number on the tire sidewall
• Look for bulges, cracks, or uneven wear
• Don't forget the spare, if you have one

Brakes and wipers

Summer storms and mountain trips both test your brakes and visibility. Long downhill stretches in hot weather can overheat brakes, so use a lower gear to let the engine help slow the car. Have the brake pads and fluid checked if braking feels soft or you hear grinding. Sun also bakes wiper blades, so replace them if they streak or chatter, and keep the washer reservoir full for bugs and road grime.

Fluids and belts

Heat thins and breaks down fluids faster. Check:

• Engine oil level and condition
• Transmission fluid, if your car has a dipstick
• Brake fluid level
• Power steering fluid, on cars that use it
• Drive belt for cracks or fraying

Towing a trailer or camper in summer heat is especially hard on transmissions. Follow your owner's manual for towing limits and service intervals.

Safety and road trips

• Use a windshield shade to protect the dash and keep the cabin cooler
• Never leave children or pets in a parked car, even briefly
• Keep water in the car for long drives
• Pack an emergency kit with a flashlight, jumper cables, and a phone charger

Many service contracts include roadside assistance, but not all do. Check yours.

A quick pre-road-trip checklist

Before a long summer drive:

1. Check coolant, oil, and other fluids
2. Test the battery
3. Set tire pressures, including the spare
4. Confirm the AC blows cold
5. Inspect wipers and washer fluid for summer storms
6. Have your coverage and roadside numbers handy

How Warranty Wizards can help

We help you compare plans from third-party providers and explain what each covers, including cooling and AC components, before you buy. If you'd like options for your car, request a free quote at /get-a-quote/.