Checking the tire pressure is very important. If your car is older with a lot of mileage, it's also a good idea to check the coolant, which will prevent your car from heating up too much when you drive for long periods of time. Also, if your car uses conventional oil, change it every 3,500 to 5,000 miles. If your car uses synthetic oil, change it every 7,500 to 10,000 miles instead.