Recently I had the same exact problem and so did my friend who bought an Aviator when I did (new in 2004). Mine only has 53,000 miles. It cost us each about $800 to repair, of which 95% was for the parts. My mechanic was quoted several prices for parts, up to $1300. We couldn't find used parts in salvage yards because they are being 'bought up' as soon as they get them. This should have been a 'recall problem! I want my money back and I believe we all should fight for a recall.
I was told by the Ford Motor Co. Customer Service (Amy) that they are not having these gear-shift problems reported to them by the car owners. I have reported mine and so has my friend. We need everyone who has had their Aviator get stuck in Park call customer service at 800-392-3673 and REPORT THIS. Maybe then they will realize it is a factory default item.....turn it into a recall item and get our money back for these ridiculous repair costs.
I just got a $950 quote to rplace broken parts in the gearshift. Mine looked up as I pulled into my garage. It stuck solid in Drive. I turned the key off and couldn't remove the key. AAA helped get the shifter to work so I could drive it to the dealer. We just returned from a long road trip in the car. We think it is a great ride but this and a crack in the transfer case gives us second thoughts on buying another Lincoln product. It's a 2005 Aviator.
Just got it back. It cost 896.54, 430 in parts, 387 in labor. No help from customer service. All I have to say is if you have a shift lever that moves up and down on the lever, take it in now for repairs.