My Crown Vic currently has 285k miles and I've had transmission issues recently. Month ago it stopped working, after giving a few hints, and the 1-2 pistons were replaced along with filter and fluid. Does okay now, except it hestitates when I gas it at high speeds, for instance if I want to go from 70 to 80. It was nonresponsive once, along the lines of how it felt when it gave out a month ago. What is the likely issue? Other pistons or something related to what they did? I wish I could give more info but transmission is definitely my weak link in auto knowledge. I don't know if this is original or whether it was well-maintained before. I do 85% highway and have put 30k miles on it in a year. Thanks guys!