Leaving things out in the sun can sometimes help air them out and clean them, especially for organic smells, b/c most bacteria/molds/mildews don't really like direct sunlight. Consider pulling the seats and leaving them sitting in direct sunshine. This may even be more effective if you pull them apart. I'm sure the foam in the seats has soaked in the crap too. Your best bet may be to try to replace the foam. Seems like you should be able to scrub on the leather in a few wash then dry cycles out in the sun. Don't overdo the sun exposure since you don't want to completely dry out or fade the leather. Sorry I don't have a more specific chemical solution for you. For carpets, again you might have most luck tossing the padding (if any). Obviously, this implies pulling the interior out of the Durango, but if you're replacing seats and such, sounds like you're already willing to go that far. Trying these steps can only cost you time and effort and may save money in the end. There's no way all new leather is cheap. Good luck.
Last edited by Dujo; 04-19-2012 at 11:12 AM..