Question about DEF:
Right now we have a pre-emissions diesel, but one day may upgrade to a later model. We live in Southern AZ, where it gets extremely hot in the summer. Our diesel truck is pretty much a dedicated tow truck. We put 6000-7000 miles per year on the truck, but between camping trips, it mostly sits in the driveway, often for 3 weeks or more at a time. My question is, if we had a DEF equipped truck, given the high heat environment here, would the DEF sitting in the tank be at risk of going bad?