Even though you had your car checked out before you left on vacation, practice good driving habits. Long periods of driving in hot weather put increased stress on your car, so you want to do everything you can to make your car's job easier.
First of all, use common sense. The general rule is to be patient: let the care warm up a few seconds before you drive away; accelerate slowly, and don't slam on the brakes. You can also improve your gas mileage by driving between fifty-five and sixty-five miles per hour.
As you drive, keep an eye on your car's gauges, and not just the fuel gauge. Your tachometer (RPMs) and the engine thermostat will often alert you to a major problem. If your engine begins to overheat, pull over and add some coolant before you continue driving. In addition, pay attention in particular to the brakes and the handling of your car. These two factors can cause major wrecks if they malfunction, so you want to notice any abnormal operation on their part.
Regularly along your trip, you should check your oil and tire pressure. To check the oil, you simply need to remove the dipstick, clean it off, and then insert and remove the dipstick again. You're simply looking to make sure the oil level is neither too high nor too low (indicator lines on your dipstick should direct you). As for the tire pressure, check the reading on your tire gauge against the suggested tire pressure (listed on the doorjamb of your car). It's also a good idea to monitor your gas mileage and to look under your hood on occasion. You probably won't be able to diagnose any problem, but you can recognize major changes, which might indicate a problem.
If you do have car trouble along the road, contact AAA (if you are a member), your car dealer, or a local car mechanic. When you get home, however, take your car in to your mechanic. Explain what happened and what, if any, work was done. Then, ask if any other work needs to be done to help ensure that your next trip is problem-free.