Does the tail    travel  beneath   any  power lines?   

I  had    similar  issues   last year  with an  older  system  too.     I   took  some    aluminum  foil  and  covered  the   shield   over the antennas.     The   galvanized  was  a lot duller than  when it  was  new,   and in my  mind,    was  allowing   too much  stray  interference  to hit the  antenna.   Shiney surfaces  should be more effective, right?

Which it was.   when it was  under a  interconnect line for  the windtower farm,  it  was  quite active  trying to follow either the buried wire, or  stray interference from above..   active enough  to  overheat the contactors in the steer system..making them stick on.. making  it to  veer and safety off.  By the time I  got out there to re-start,  the contactors  had cooled off,  and   resumed normal function  for  another  15 minutes.      
The  foil all but  eliminated  the 'hunting'... which  should  help the longevity of the  new  contactors.  

each time,   I  had  err 08,  and   4 trips  from service  guy  replacing the antennas.    Each time  I'd ride  on the  steer tower, manually  steer it  back,  and   all was  good  until  it   heated up again,  usually  less than   15-20 minutes.
  I finally argued enough  and   got him  to  replace those switches..   Been working fine since.  



I'm not  convinced though  it was  'taking out'  my antennas..  in  fact,   I'm  not  sure all of the ones he replaced were bad.
    If  you  don't have  any power lines,    have you been getting  lot of  lightning storms?