Last year I had a sensor go out and lost my TOD. Bought the sensors, had them installed and then had 4 wheel all the time. To make a long story short one of the new sensors was bad and the dealer (now Hyundai) wanted about $1300 to fix it. I contacted Isuzu Customer Service with the dealer estimate and they not only agreed to send new sensors but paid for the repair. Not bad for a 14 year old vehicle.