I found an excellent site that shows all the FCC rules and regulations concerning CB radio. It can be found at:

http://www.berniescb.com/fccfacts.htm

AM CB radios can only output 4 watts. SSB CB radios can output 12 watts. If you plan to install a CB in your truck, you are responsible for what you put on the air. The FCC doles out LARGE fines for blatant radio offenders (when caught).