Thanks Swoop -

sometimes tech's will loosen up the articulation to allow for more wheel wear and keep this from happening.
It sounds like you have a couple choices, either put the articulation back to where it was or buy a new drive tire ;o)

Keep in mind setting the articulation outside of the factory specs does make the machine less stable and could lead to a tipover so for safety sake buying a new tire would be the way to go imo.