According to Karen Guregian of the Boston Herald, Wilfork was so disillusioned about his situation that he not only asked for his release, but cleaned out his locker.

Wilfork was bothered by the fact the Patriots asked to restructure his deal, rather than pay the 31-year-old $7.5 million coming off a torn Achilles.
Citing two sources, Guregian reports that Wilfork ripped his nameplate off the locker as well.

http://profootballtalk.nbcsports.co...fork-cleaned-out-his-locker-after-asking-out/