alignmet? or something else

[acjjkamp]

I took the truck in to the dealer for the recall, haven’t noticed any change in that end of it.
While it was in I had them change the oil and rotate the tires ($126 ouch).
Now the truck is pulling to the left a little, and the steering wheel needs to be held right to keep a straight line. The tires are inflated correctly, never had alignment problems before.
Question is: Why would this start pulling after the rotation? There isn’t anything that I know of that would cause this. Would an existing alignment problem surface after a tire rotation, or did they go out 'crawling' for the test drive?
side note: the tires are the 18" Conti's

 

[Tx_Atty]

uneven wear will cause a pull. Check the tire tread to see if they all match and look for uneven wear on any single tire. It is possible the alignment is out just enough to cause the wear but not be noticeable until you put a better tire in the right spot.