Ford has had major problems with the transmissions in the 2005-2006 Ford 500's. The transmissions go out with as little as 30,000 miles on the vehicle. My car is no exception to the transmission issues. The car will "buck and jump" when passing or when slowing below 40 mph. I contacted Ford and their response was since the NHTSA hasn't forced a recall, there is nothing they can do to assist with the problem. Instead of being proactive, I suppose Ford will just wait until enough people have had their fill of problems and file class action lawsuits.
Bought my 06 SEL FWD used for $5000 recently and can tell you it's the absolute BEST BUY I've ever made for a used vehicle. I had the 07 Limited AWD for a couple of years (also used) and in retrospect probably should not have sold it. It was great in the (Michigan) winters, got super mileage for a big car (26+ highway), seated 5 adults comfortably and the only issue I had was with the rear brakes wearing out after only 15K miles. This recent 2006 purchase reminds me of the great qualities that Ford built into these vehicles and had they been "faster" and perhaps a bit cheaper (than the $30K price tag for the Limited AWD), they'd probably still be around.
I originally bought this car in 2012 with 62k miles. Now it's 2015 and 163k miles later. My car has the cvt transmission and no issues. Those complaining of slipping or hard shifts in between gears would be the 6 speed auto. Cvt transmission had only one continous gear. It does not shift. The only replacements done to this car other than normal maintenance is replacing the alternator at 120k miles and replacing the starter at 150k miles. Otherwise a solid car for the money. My daily commute is 120 miles round trip.
I'll be honest I'm in the automotive industry and 15 years ago I was the last person backing a Ford product. However I was talked into an F150 and fell in love. Now on my second Ford, this one the Fivehundred. I know there are some bad reviews on the transmission but I was fortunate and didn't have any issue's until just recently 242k. Of course it's an extremely expensive repair ( we do not work on transmissions ) . I love my car, and to me it's worth the fix. I am not a gentle driver and drive 100 miles a day for work so I am shocked no issue's until now.,but very grateful as well. I would buy another one in a heart beat.