Section 506. Payment of tax

1. At the time of filing a return, as required
  by this article, each carrier shall pay to the tax  commission  the  tax
  imposed  by this article for the period covered by such return. Such tax
  shall be due and payable at the time of  filing  the  return  or,  if  a
  return  is  not  filed  when due, on the last day on which the return is
  required to be filed.    The  tax  commission  may  grant  a  reasonable
  extension of time for paying the tax whenever good cause exists.
    2. The fees, taxes, penalties and interest accruing under this article
  shall  constitute  a  lien  upon  all motor vehicles and vehicular units
  which are owned by such carrier or of which he has  the  lawful  use  or
  control.  The  lien  shall  attach  at the time of operation of any such
  motor vehicle or vehicular unit  within  this  state  and  shall  remain
  effective until the fees, taxes, penalties and interest are paid, or the
  motor  vehicle  or vehicular unit is sold for the payment thereof.  Such
  liens shall be paramount to all  prior  liens  or  encumbrances  of  any
  character  and  to  the rights of any holder of the legal title in or to
  any such motor vehicle or vehicular unit, provided, however, that:
    a. No lien for any additional tax assessed pursuant  to  this  article
  shall  be  enforceable against any motor vehicle or vehicular unit which
  prior to such assessment had been transferred in good faith  to  a  bona
  fide transferee for value.
    b.  The  lien  of  such  tax  shall  be  subject  to  the  lien of any
  indebtedness  secured  by  a  chattel  mortgage  or  conditional   sales
  agreement existing against such motor vehicle or vehicular unit previous
  to the time when such tax became a lien, if:
    (1)  Such  indebtedness was incurred in good faith to secure a portion
  of the purchase price of such motor vehicle or vehicular unit, and
    (2) Such indebtedness is secured by a chattel mortgage or  conditional
  sales agreement duly filed as required by law, and
    (3)  Such  chattel  mortgage  or  conditional  sales agreement was not
  given, directly or indirectly, to any  officer  or  stockholder  of  the
  corporation  owning  or  having  the lawful use or control of such motor
  vehicle or vehicular unit, whether  as  a  purchase  money  mortgage  or
  otherwise.
    The  lien  of such tax shall be enforceable, however, as to any equity
  after the encumbrance of such  chattel  mortgage  or  conditional  sales
  agreement.  In  the  event  a motor vehicle or vehicular unit subject to
  such tax lien is repossessed by a chattel  mortgagee  or  a  conditional
  vendor  such motor vehicle or vehicular unit shall not be sold at public
  or private sale unless at least five days notice of the time  and  place
  of  such  sale  is  served by registered mail upon the tax commission in
  Albany.