Recreational Vehicle Lpg Tank Valve/gauge problems of the 2007 Nissan Murano

The battery has been replaced twice in the vehicle and it has less than 35,000 miles on it. The first replacement was done when the car was only about 6 months old and I just recently had to have the battery replaced again. The second battery was supposed to be an 84,000 mile battery and was under warranty. However, when I was driving it, the car died on me and would not start again. The battery had less than 26,000 miles on it. Nissan fought us on the replacement even though it was under warranty, but we finally got another one put in. We are on our 3rd battery in less than 3 years. This same vehicle had an engine mount crack at 32,000 miles and has also had the radiator replaced at 34,000 miles. It has been in the shop 4 times now in the last 2 1/2 months. When the radiator went out, the gauges did not even say that the car was running hot. I discovered the issue when my car started smoking everywhere and coolant was all over my vehicle. Nissan insists that it is not an electrical issue of any kind and that the gauge can still read cool if the radiator goes out and the car is smoking. All in all, I now have the 3rd new battery, a new radiator, and a new engine mount. The drive belts have also cracked, but Nissan refused to do anything about that.