I’d like to keep extra water in my Tahoe, especially since we live in a desert. I have dozens and dozens of 2-liter bottles filled with water that I could easily place underneath the front and back seats, but I’ve read that heat can cause problems for food and water stored in that type of plastic. Any other suggestions for water storage?
How about just buying a 6 gallon water jug and changing the water 2 or 3 times a year.
As far as health problems from the container/s, remember that you are never going to drink it anyway, if you ever do then it will only be once in your life and it will be an emergency and it won't have any negative effect on you at all. Don't obsess too much on things like that, just make sure that you have some form of water in the car.
We tie down one the nice stainless coleman coolers in our landcruiser. Store bottles of water in that.
Such keeps at bay what ya mention. We swap out water each month. Water the garden.