Brakes:
If you hear any grinding noises or feel unusual vibrations when you apply the brakes, or if the vehicle pulls to one side, take the vehicle in for a comprehensive checkup. It would be a good idea just to have your brakes looked at to be sure they won't need replacing 1,000 miles into your trip.

Cooling system:
Sustained high speed driving and hot summer days combine to put a lot of stress on an engine's cooling system. If your vehicles is using conventional green anti-freeze and hasn't been flushed for two years, now is an excellent time to do it. If it has extended life anti-freeze go with the manufacturers recommended change intervals. If this interval occurs during the trip, do it now. The cooling system should be refilled with a 50/50 mix of new antifreeze and water. Don't refill with just straight anti-freeze. If the system needs to be flushed, it is a fairly easy job for a DIY. Just make sure you put the old antifreeze in a container and take it to a proper recycling location.

Air-conditioning:
Make sure your car's heating and A/C is working properly. Run it for a while in each of its operating modes and check that the airflow is coming from all appropriate vents. If the A/C system takes an inordinately long time to cool the inside of the car, or if the air never gets cold enough, the system probably needs to be checked for leaks and recharged. If the A/C smells like your sons gym socks, the drain hose is probably clogged or restricted.

While following this list of checks and inspections are a good idea, you should be aware of other, more general warning signs as well. Ticking, clunking or knocking noises, a sudden vibration or shimmy, or anything out of the ordinary is probably a symptom of a hidden problem that should be checked before hitting the road.

Keep in mind that no matter how careful and thorough you were in doing your pre-trip preparations, unexpected problems can still happen. So it is a good idea to have some basic emergency gear onboard in something does happen. Jumper cables, flares, a disposable, pre-paid cell phone, a gallon of anti-freeze, a gallon of water, three quarts of oil, a couple of quarts of ATF and a couple of gallons of bug juice can be worth ten times their weight in gold when you need it 50 miles from nowhere. Another good idea is to make a check list of things to check when you make a pit stop so you can be sure to cover all your bases. Do these simple checks and what happened to the Griswalds will not happen to you.

And finally, not only can a pre-trip inspection help reduce chances of costly and possibly dangerous road trouble, it also provides an opportunity to have needed repairs made at home, with your own technician who knows your vehicle. Especially important, it provides peace of mind. While no inspection can guarantee a car's performance, it's comforting to know proper precautions were taken.