I have a 2009 Lincoln MKX. I love it but the weak link and huge under engineering blunder by Ford on mine and several other Ford models is the PTU being esse sealed. It has a fill plug but no drain. I had mine serviced about a year ago as it was leaking. My mechanic flushed, filled and installed a new seal. It's fine but I know it needs to be suctioned and filled with fresh syn 75w-140 fluid. The local Valvoline quick change place claims to be able to provide this service.... Around $100, which I think may include both differentials as well. Anyone take their Ford product to these guys or any other place to service the PTU?