Reverse and subtract
Pyth, 5 bytes
4 bytes thanks to FryAmTheEggman
uas_`

Test suite.
The truthy value is one of the numbers in the loop.
The falsey value is 0.
Explanation
uas_`      Input:Q
uas_`GGQ   Implicit filling of variables.

u      Q   Set G as Q: do this repeatedly until result seen before: Set G as
 a             the absolute difference of
     G             G
    `              convert to string
   _               reverse
  s                convert to integer
      G        and G