Half-filled water tanks

Actually, the answer should be:

no & possibly - a lot of water tank have in built baffles

Are you pessimist or an optimist?? THAT is the question.

I think that one slipped by Allan

If you start your journey with the water tank half full then you are really starting a trip half empty!! Do you have 2 X 9KG Gas bottles fitted? You could take one of those off & there is 18KG saved if it's full of course.

That's a good call David. We met a guy crossing the blue mountains. He was in an older nissan towing a large caravan (too big for his car IMHO). He had blown a radiator hose. There was steam going every where and it was whistling and crackling away. We pulled over to offer some help. He had blown the hose at the bottom of the hill and had topped it up with all the water he had in his thermos, which was about a cup full. I asked why he didn't use the water out of the van. He said it is to heavy for the car with water in the tanks, so they empty them before they head off. We topped him up and gave him some coolant. He didn't have anything to repair the hose with either so we fixed that.
We followed him into town and by the way the engine was whistling and making funny sounds I don't think he was going any further. All because he had no water in his van.
If it is that close them get a bigger car or smaller van.

Josh

When you think about it – that makes a lot of sense.

Another point on placement of water tanks, is that they can make for a more stable tow with them forward of the axle with the weight over the tow bar.

The one water tank listed by PeeKay won't keep two people in water for long, even just for drinking water. One week perhaps, even they didn't cook or shower with the water without topping up.

I think you will find good manufacturer's fit baffles to their tanks although they may not be obvious.

In the case of poly tanks the baffle is formed by a depression moulded in the top of the tank toward, but not touching the tank bottom. This baffle depression would not be visible on a tank installed below the van floor.

The depression baffle is visible in the picture below.

Image Could Not Be Found

Many thanks Allan for this info. We'll check this out with the dealer.