Had to send ours in 7 times in 6 years for "service" cost me the UPS charges and return UPS most times ($80-$90 round trip) many times it was the air lines or regulator, sometimes the control board. Solved our problem when it stopped working two weeks after getting it back the last time. Now have had a Blue Ox Patriot for 5 years. It to has gone to the factory service center twice, both times for a failed battery. Once under warranty once at my cost. Now after being well out of warranty, next time I'll break the "warranty seal" and replace the battery myself, about $30.00. I now charge the battery on the unit every other night when traveling, since the last battery failure.