Sorry to hear about your noise problem. I do not own an F-150, however, this vehicle has a well documented history of the fuel pump causing EMI/RFI.
I understand you want an "easy" fix, but unfortunately, I am not sure that one exists. Here is a small start.
If you do a Google search with "Ford F-150 RFI" you'll get some decent websites to check out such as http://www.arrl.org/tis/info/fuel.html http://www.eham.net/forums/MobileHam/778
(an older thread from this website) http://www.mindspring.com/~nx7u/mobile/noise.htm
(Scott's website is excellent-check it out. His station is in an F-150.) http://www.k2bj.com/Pages/Noise/Intro.htm
(Brian's website is also chocked full of information)
Hope that helps. I would have to say that part of the fun and frustration of mobile HF is not just the operating, but working through and solving some interesting installation problems that you do not encounter with your home setup.
Good Luck and 73-