1. DO NOT TAKE ANY PETS!!! You will end up having to quarantine them at the first border crossing. Then if you do wait for two weeks at each border crossing, pay the "fees" etc, good luck getting it back into the US after driving to Rio and back! (I've had friends tell me that in arduous trips across Siberia, China, South America, etc. often the biggest PITA is getting back into the US!)

2. Do NOT take any "medicinals" unless you have a VERY CLEARLY WRITTEN prescription from a doctor for it/them. Even if you do, expect to be charged a special "fee" for being allowed to keep them if stopped.

5. Glue/weld everything loose that can be taken off your car, like license plates (a favorite target), mirrors, hubcaps, etc. I have friends that actually had "copies" of their license plates made in Mexico, and used those, keeping the real ones safe inside the car.

6. Spanish will do you more good than Portuguese, since all the countries you will pass through speak Spanish. You can learn Portuguese while you are cooking in Rio! :-)

7. Make sure you have enough money to make the trip. Have pre-arranged places along the way where you can have money wired to you by people in the US. You definitely DON'T want to carry all your money with you. (Or you could end up like a friend of mine who got robbed on a surfing trip in Costa Rica, and they took EVERYTHING - including his clothes. He had to walk about 4 miles buck naked into the next village, where he was promptly picked up by the police. Needless to say, it took him a while to explain the situation. After about three days in jail (he had no money for a hotel), some other Americans learned about him and helped him out so he could get back home.

8. Bring a spare of everything - tires, CV joints, ECU, etc. You may find them VERY hard to locate on your journey. My general rule is that if some local with a welder and some basic equipment can't fix it or fabricate a new one, bring along a spare.

I have made many trips to Mexico, Guatemala, Belize, and Costa Rica, and have never had any serious problems. (Other than "La Mordida" - the "bite" as it is called - small bribes)