The book, set to come out Friday, bad-mouths McCain's wife, Cindy, and daughter, Meghan, characterizing the duo as paranoid and often overbearing.
In the book, portions of which can be found on the Amazon website, Palin writes that she "had a sneaking suspicion I might need to watch my back" when dealing with the McCain women and that Cindy and Meghan gave her a pompous cold shoulder upon their first meeting.
"Every time we saw Meghan, she seemed to be constantly checking us out, comparing my family to hers and complaining," Palin writes. "Oh the complaining."
She also claims Cindy "held herself like royalty" and demanded to be the godmother of her 2-year-old son and one of the first to hold him after his birth.
Palin then turned her malicious pen on her ex-fiancée, lambasting him for his inability to keep it in his pants.
In addition to calling him a "gnat," Palin writes, he "cheated on me about as frequently as he sharpened his hockey skates."
Also included in Palin's Pandora's Box is the tragic yarn of how she drunkenly lost her virginity to Johnston on a camping trip.
Apparently it was a little underwhelming. Palin writes the experience "wasn't that meaningful" to her.