To all who intends to travel through Brazil using a Garmin GPS.
Don't rely on Garmin's map of Brazil. You'll, get hopelessly lost...
Here's a link to a website that has a GREAT (FREE!!!) map of Brazil. It has all the big cities BUT also a lot of the very small dirtroads that don't appear even on the paper maps. http://www.tracksource.org.br/
I never leave home without it. It always gets me where I want to go (and back...)
The site is in Portuguese, but I'm sure somebody here can help translating if necessary
I thought this could be useful.