Out of nowhere my 2001 Wrangler has started vibrating as soon as I push on the gas. I got under it and the rear where the slip yoke is at the transfer case the u-joints are touching. All of the other ones seem to be fine.
Replace them with the Spicer 5-1310x u-joint. That is a direct replacement that is both stronger and more durable than the lighter duty Spicer u-joint the factory installed.