Kathryn Bird explains that yes, you can drive with a full water tank, but 1 litre of water weighs 1 kg, so a full tank adds serious weight that increases fuel use and braking distance. She recommends filling up at the campsite instead, or carrying only half a tank for wild camping.
Can you drive with a full tank of water in your motorhome? The short answer is yes, but there are 2 things that I want you to think about. Number one, have you got the capacity in your payload? If you imagine that a litre of water is 1 kilogram, give or take, that is a lot of weight to go into your payload, and if you go over your maximum weight, it will invalidate your insurance. The second thing that I want you to think about is your vehicle weight. Obviously, if you travel with a full tank of water, your vehicle becomes heavier. This will mean that it will cost you more in fuel to get to where you're going, But also you need to do things like leave bigger braking distances because you're a heavier vehicle. My advice if you're going to a campsite is to fill up when you get there and travel with an empty tank. If you're going to be doing wild park-ups, it's obviously a bit more difficult. Maybe look at traveling with half a tank instead of a full tank and just filling up a bit more often. Hope that helps. Thanks, Kathryn.
