Yes, the Dead’s jazz influences don’t show up as consistently as with the ABB, probably because their music encompasses a lot more different musical styles and genres. But you can certainly hear it in songs like Eyes of the World, Bird Song, Crazy Fingers, and some versions of Dark Star. And the band would swing a lot more when Kreutzmann was the sole drummer for a few years in the early 70s.
Garcia played a lot more in the jazz vein with his own bands, especially with Merl Saunders and Howard Wales. He did some great versions of My Favorite Things with Merl. And of course, you also have Jazz Is Dead, which showed how many Dead songs could be adapted and played more 'jazzily' if that's a word.