Do I wait and have PTU replaced for second time in 6 months...what are my rights on 2008 Ford Edge

feels like entire back end going to fall off.. when driving..horrific jerk,,, momentary,, repeats,, dealer says cannot drive it,,,got rental... Dealer wants $$$$ to get me another car.. I feel I should get same car,,poss newer or of equal value,, and no $$$ output....
there is thousands back ordered

Asked by for the 2008 Ford Edge
I know this is an old question but as of today (2015) Ford offers a two year warranty on parts and labor on major parts. Also, if it "feels like the back end is going to fall off" that seems unusual since the PDU is up front. This is a major problem on all wheel drive Ford Edge/Flex/500