As long as the Park Ave is not supercharged it will likely fit. That is not to say it is the correct transmission though. There could be differences in the electronics from year to year which affect the way it will shift etc. Search both cars online to see what model of transmission was used. You may also want to consult a shop to confirm the compatability of the two different years. Changing them out is a ton of work and you don't want to end up doing it twice.
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